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BRITISH CONCIIOLOGY,

OR AN ACCOUNT OF

THE MOLLUSCA

WHICH NOW INHABIT THE BRITISH ISLES AND THE

SURROUNDING SEAS.

VOLUME III.

MARINE SHELLS,

COMPRISING THE REMAINING CONCHIFERA,
THE SOLENOCONCHIA, AND GASTEROPODA AS FAR AS

LITTORINA.

By JOHN GWYN JEFFREYS, F.R.S., F.G.S., &c.

LONDON:

JOHN VAN VOORST, PATERNOSTER ROW.

MDCCCLXY.
[ The right of Translation is reserved.]

riUNTEl) BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET.

\7

Family XVI. SOLE'NIDjE, Latreille. ' ^

Body elongated in a transverse direction : mantle closed in
front, with its borders adhering together, open at the anterior
end for the passage of a foot, and forming at the posterior end
t\to conical tubes or siphons of different lengths, which are
more or less enclosed in a common sheath : gills two on each
side, long and narrow : palps corresponding with the gills in
number and position, long, slender, and triangular : foot large
and muscular, adapted for burrowing in sand.

8hell shaped like the body, equivalve, open or gaping at
both ends: epidermis strong and persistent, overlapping the
front or ventral edges of the shell : beetles small : ligament ex-
ternal : hinge strengthened inside by a ridge : teeth consisting
of one or two thorn -like cardinals in each valve, which are
erect, curved, and interlock ; laterals partly recumbent, in
some cases rudimentary or wanting : muscular scars irregular :
pallial scar sinuated.

This and the succeeding families of marine Conchifera
differ from those described in the second volume in
having the mantle more or less closed in front. Pro-
fessor Oken imagined that, in a biological point of view,
they typify the Nudibranchs and Salpse; but he gave
no reason for this fanciful analogy. Although the
SoJeniclce appear at first sight to constitute a natural
and simple group, it will be found to comprise certain
forms which connect it with other families. This resem-
blance has probably misled some systematists, and in-
duced them to associate with Solen such very dissimilar
genera as Psammobia, Lutraria, Panopaa, and My a.
The structure of the hinge, however, will always serve
to distinguish any one of them from the rest.

Dr. Carpenter says that the external layer of the
shells in the present family is composed of cells which

VOL. III. B

75034

"A SOLENIDiE.

form elongated prisms, with walls as straight and parallel
as those of Pinna ; but their axes are nearly conformable
with the surface, cropping out somewhat obliquely upon
the exterior, where their rounded terminations with
distinct nuclear spots may sometimes be seen. The
internal layer is very dense, and nearly homogeneous ;
but evident traces of cells are occasionally to be met
with. Most of the Solen tribe are littoral, and live in
sand which they penetrate for that purpose ; a few are
found at various and often considerable depths of water,
and these prefer a more muddy habitat. None of their
remains have been discovered in any geological formation
older than the lower tertiaries.

Genus I. SOLECUR'TUS * De Blainville. PL I. f. 1.

Body oblong, compressed : mantle capable of being inflated
in front : tubes partly separated, extended, and occasionally
strangulated, issuing from a common sheath : foot tongue-
shaped, of an enormous size.

Shell resembling in shape a kidney bean, rather solid, nearly
equilateral, concentrically striated or sculptured diagonally
with imbricated ribs : teeth, two cardinals in the right valve,
and one in the left ; laterals short and rudimentary : pallial
scar having a broad and shallow fold.

For the reasons which I have given in the last volume
(pp. 327 and 434), with respect to the systematic value
of characters derived from the separation or union of
the pallial tubes, I prefer not placing this genus and
Ceratisolen in one family, and Solen in another. The
relations of Ceratisolen to Solen, through S. pellucidus,
are too close to warrant their being assigned to different
families, and the transition from the last-named species
to S. ensis is very slight and gradual.

* A short Solen.

SOLECURTUS. 6

It is the genus Macha of Oken, who described it in
the c Allgemeine Naturgeschichte ' for 1835, giving the
Solen strigilatus of Linne as the type. This, however,
was eleven years after De BlainvihVs publication of Sole-
cur tus. Herrmannsen at first cited the date of Oken's
publication as 1815, but corrected the mistake in his
' Supplement ;' he disapproves of the word Solecurtus, as
well as of Solenocurtus and Solenocurtis (emendations
of Sowerby and Swainson), and suggests Cyrtosolen.
But if we proceed in this way to rectify the nomenclature
of Natural History, few of the modern names would be
recognizable in their new dresses. A century ago Linne
complained of a deterioration in this respect — one of his
axioms being " Veterum nomina plerumque prsestantis-
sima, recentiorum pejora fuere." I fear that the lapse
of time has not brought with it any improvement. The
present name appears to have been compounded accord-
ing to a grammatical rule called Syncope, and it has a
precedent in the word lapicida (for lapidicida) used by
Livy and Varro. Leach's name of Azor appeared in
the second edition (1844) of Brown's work on British
and Irish Conchology; it had S. antiquatus for its type.

1. Solecurtus can'didus*, Renier.

Solen candidus, Kenier, Tav. Conch. Adriat. p. 1. Solecurtus candidus,
F. & H. i. p. 263, pi. xv. f. 1, 2.

Body of a uniform bright orange-yellow colour : mantle
somewhat paler towards the margin : tubes united at their
bases, where the siphonal mass is large and thick, and sepa-
rated at their extremities ; orifices fringed : foot pale orange
with a whitish sole.

Shell elliptical, rather convex, but compressed in the middle,
solid, opaque, somewhat glossy : sculpture, 40 to 50 oblique and
imbricated longitudinal striae or slight ribs, of which nearly

* White.

b2

4 solenid^:.

two-thirds cover the ventral or front part of the shell, and
radiate from the beak, the rest occupying the whole of the
posterior side, and diverging- from an angle formed by a junc-
tion with the first-mentioned set of striae ; this angle varies
from acute to obtuse, according to the number of striae ; the
anterior side is not thus striated ; the surface is also covered
with minute and crowded longitudinal stria) resembling those
observable in species of Psammobia : colour pale yellowish-
white : epidermis like oil-skin, yellowish with a brown tint in
aged specimens : margins slightly incurved in front, obliquely
truncated with a rounded contour at each end, nearly straight
behind and parallel with the front, except in the middle, where
the beak forms a projection equal to the indentation on the
opposite side : beaks pointed and nearly straight : ligament
chrysalis- shaped, prominent, dark horncolour : hinge-line
straight : hinge-plate thick and strong, reflected over the
ligament and abruptly truncated at the posterior end : hinge
supported by a strong oblique shelf-like rib : teeth, in the right
valve two blunt cardinals curving upwards from below the
beak, the posterior being much larger than the other ; the
left valve has a similar cardinal on the anterior side, besides a
short, triangular and oblique lateral on the posterior side :
inside chalky- white, with a slightly nacreous gloss in some
parts, incipient pearls being occasionally formed on the
inner edge of the mantle ; margin blunt : pallial sear well
defined ; sinus oblong, and extending two-thirds across the
transverse diameter of the shell : muscrdar scars distinct ; an-
terior irregularly pear-shaped, posterior triangularly oval.
L. 0-9. B.l-9.

Var. oblonga. Shell narrower in proportion to its breadth.

Habitat : In sand, between low-water mark at spring
tides (Lukis), and various depths seawards, from 20
to 85 fathoms, on different parts of the coast from the
Shetland to the Channel Isles, but local ; more common
in Bantry Bay than elsewhere. Var. 1. Guernsey
(Lukis) • Polkernow Cove, Cornwall (Miss Lavars) ;
Shetland (Barlee) . Believing it to be the Solen multi-
striatus of Scacchi, I find it recorded as a fossil from the
neighbourhood of Antwerp, and from Gravina in Apulia.
Lamarck and Brocchi appear to have mistaken a white

SOLECURTUS. O

variety of S. strigilatus for this shell. Its foreign
distribution comprises the coasts of France, Spain,
Portugal, Italy, Algeria, the Canary Isles, and Madeira.
All that is known of the habits of this pretty species,
we owe to the Rev. R. N. Dennis, who informs me that
he was greatly surprised, when at Herm, with its
activity — adding, " A couple of specimens which I had
in a milk- pan of salt water were on the crawl whenever
I looked at them, really travelling at a great rate for
mollusks, and, without the least respect for their neigh-
bours' comforts, walking over, and upsetting all the
weaker shell-fish which were with them."

I have retained the specific name candidus because it
is now generally accepted; but the Solen candidus of
Renier may have been only a white variety of Solecurtus
strigilatus, a rather common Mediterranean shell. His
description is too scanty for identification, and he does
not even give the last-named species as an Adriatic
shell. This variety was noticed by Limie in his ' Mus.
Ulr. Reg/ Olivi was at first inclined to consider it a
distinct species, but after finding intermediate specimens
he reduced it to the rank of a variety ; it was enume-
rated by Chiereghini also from the Adriatic under the
name of Solen albicans. The present species is the
Psammobia scopula of Turton, and Adasius Loscombeus
of Leach. I have been asked why I notice any of the
bizarre names given in Leach's ' Synopsis of the Mol-
lusca of Great Britain/ since they are quite disregarded
by British naturalists. I cannot, however, forget that
it is a published work, and has been circulated on the
Continent. There I know that these volumes have also
found a place; and if I were to ignore the works of
Leach, Brown, and other authors on the subject of
which I treat, I feel that I should stand justly accused

6 SOLENIDiE.

of having neglected the writings of my own countrymen,
and of having thus caused some confusion or inconve-
nience to those who study the European Mollusca. I
do not regret the trouble I have taken in making this
concordance, hoping and believing that it will save the
labour of my fellow- workmen. Turton must have been
mistaken in saying that S. strigilatus had been dredged
in Torbay, and found by General Bingham in Cornwall,
and by Mrs. Loscombe in the Scilly Isles. The collec-
tion of that lady was sold by auction about 25 years
ago, when I purchased, through the late Mr. G. B.
Sowerby, all the supposed British Shells contained in it.
Among them were specimens of S. strigilatus and many
other undoubtedly Mediterranean species, as well as a
few from the Arctic seas. S. strigilatus is a much
larger shell than S. candidus, and usually rose-coloured
with two white rays.

2. S. antiqua' tus*, Pulteney.

Solen antiquatus, Pult. Cat. Dors. p. 28, pi. iv. f. 5. Solecurttis coarctatus,
F. & H. i. p. 259, pi. xv. f. 3, and (animal) pi. I. f. 5.

Body rather compressed, entirely white : mantle having its
edges fringed with short cirri : tabes capable of being inflated
to three times their ordinary diameter, united for a considerable
distance from their bases, and separate at their extremities ;
orifice of the branchial tube cirrous, that of the excretory one
plain : gills partly lodged in the lower portion of the siphonal
sheath, the upper pair much shorter than the other : palps
distinctly pectinated within, and less so on the outside : foot
thick and fleshy.

Shell elliptical, with an oblique outline, compressed through-
out, but especially in the middle, solid, opaque, slightly glossy :
sculpture, numerous and irregular concentric stria?, and minute
longitudinal lines like those in S. candidus, but much less
distinct ; the surface is also covered with equally minute and

* Decayed.

SOLECURTUS. 7

close-set oblique striae, which appear to be impressed by the
persistent epidermis : colour chalky-white : epidermis yellow-
ish-brown, wrinkled at the sides and composed partly of
delicate fibres, which are obliquely arranged : margins and all
other characters as in S. candidus, except that the hinge-plate
is not so much reflected, the principal or larger cardinal teeth
are jagged at their crowns, and the pallial sinus is broader
and not so long. L. 1. B. 2-25.

Habitat : Sand in 4 to 50 f., on all our coasts, al-
though sparingly. Fossil in the raised sea-bed at Belfast
(Grainger), and in the Coralline Crag, as well as the
Italian upper tertiaries. Bohuslan appears to be its
most northern limit, and the Canary Isles the most
southern. It also inhabits the intermediate district
and both sides of the Mediterranean, the Adriatic, and
iEgean, at various depths ranging from 4 to 40 f.

" We have seen it break up its tubes voluntarily into
fragments, in the manner of the Mediterranean Sole-
curtus strigilatus" (F. & H.). Clark says that the
animal, when in confinement, exserts the belly of the
mantle, inflated by water, beyond the margin of the
shell j but the instant it is irritated, it can place every
organ a I'abri. The shell differs from that of S. can-
didus in being flatter and wanting the divaricating stride
or ridges.

The Solen coarctatus of Gmelin (from a figure in
Chemnitz) is described as inhabiting the Nicobar Isles,
and does not appear to be the present species. Our
shell is the S. cultellus of Pennant, but not of Linne.

I do not believe that Siliquaria bidens, Chemnitz, is
a native of our seas, the only testimony in favour of it
being that of Pulteney, Boys, Laskey, and Turton. It
is the Solen fragilis of the three first-named authorities,
and Psammobia tceniata of the last, as well as the Solen
divisus of Spengler. The locality given by Chemnitz is

8 SOLENID.E.

the Nicobar Isles. De Gerville included it in his list
from Brittany under the name of Solen pellucidus ; and
I was informed bv M. Cailliaud that it had been taken
alive on that coast. Gould considered that it might be
the Solen centralis of Sav, a common North- American
species ; but this is very doubtful.

Solen gibbus, Spengler, was recorded by Dr. Turton as
British, under the name of S. declivis, Mrs. Loseombe
being supposed to have found a specimen in the Scilly
Isles. It is a West-Indian shell, and known as S. Gui-
neensis, Chemnitz, and S. caribbceus, Lamarck. This
species is likewise described by Gould as North-
American.

Genus II. CE'RATISO'LEN *, Forbes. PI. I. f. 2.

Body oblong, flattened : mantle slightly projecting above and
below on the anterior side : tubes for the most part separated,
and considerably extended : foot conical, and capable of being
expanded into a club -like form.

Shell resembling a bean-pod in shape, thin, nearly equi-
lateral, sculptured in the middle with extremely fine striae,
which radiate from the beaks : lunge strengthened inside by a
short rib, w T hich diverges obliquely from the beak in each valve
towards the front margin : teeth, one cardinal in the right, and
two in the left valve, besides short but distinct laterals :
pallial scar broad, with a shallow fold.

Ceratisolen is a connecting link between Solecurtus
and Solen. Its shell has the shape and nearly central
beaks of the former, and the texture and teeth of the
latter ; but it differs from both in the hinge being
strengthened by internal cross ribs. The animal has
its mantle-tubes separate and extended as in Solecurtus.
No other species appears to be known except our own,

* A pod-shaped Solen.

CE RATI SOLE N. 9

although the Pharella of Gray is closely allied to Cerati-
solen. The present genus is considered by some authors
synonymous with Pharus of Leach, originally a manu-
script name, and since made to a certain extent intel-
ligible in consequence of Dr. Gray having cited, in the
British Museum Catalogue of Mollusca, "Solen legumen"
as the type or example. But, in a scientific point of
view, it does not seem to matter much whether the
name of any group is merely manuscript, or inadequately
defined. In order to constitute a genus, it is not suffi-
cient for any naturalist, even if he should be gifted with
an eagle-eye, to pounce upon a certain species and say,
" That 's my genus so and so." Something more is
wanting. He ought to describe its characteristics, or
at all events point out in what respects it can be distin-
guished from other genera. I fully concur in the re-
commendation of the British Association Committee,
' ' that new genera or species be amply defined ; " and
one of the grounds of this recommendation seems also
to be reasonable, viz. that a large proportion of the
complicated mass of synonyms, which has now become
the opprobrium of zoology, has originated from the
slovenly and imperfect manner in which species and
higher groups have been defined. A name accompanied
by a sufficient description or diagnosis, and adopted by
naturalists of recognized authority, supersedes in my
opinion a prior name which, from the want of such ac-
companiment, was in fact "vox et prseterea nihil."
Ceratisolen has also euphony on its side. " Ejusmodi
vocabula Grseca lingua pulcherrima sunt." (Linnets
' Philosophia Botanica/ § 222.)

B D

10 SOLENID.E.

Ceratisolen legu'men *, Linne.

Solen legumen, Linn. S. N. p. 1114. Ceratisolen legumen, F. & H. i.
p. 256, pi. xiii. f. 2 (as Solen legumen), and (animal) pi. I. f. 4.

Body compressed,, yellowish -white : mantle suffused with
red : edges of the open part fringed in front, but not at the
sides : tubes rather long, for the most part separate and
diverging, of a reddish hue ; orifices cirrous : foot reddish-
purple ; when contracted it is oblong and truncated, and when
extended the extremity becomes club-shaped.

Shell pod-shaped, smaller at the anterior than at the
posterior extremity, semitransparent, glossy and partially iri-
descent : sculpture, numerous and fine but irregular striaB in
the line of growth, and a few slight and minute longitudinal
strise in the middle, which radiate from the beaks to the
front : colour pale yellowish-white ; epidermis like oil-skin,
yellowish-green or sometimes light orange, puckered by the
radiating stria? : margins nearly straight in front and behind,
curved obliquely upwards at the anterior end, and rounded at
the other end ; the dorsal compartment or area appears to be
separated from the ventral part in consequence of the epi-
dermis being thinner and of a paler hue : bealcs blunt, inclin-
ing a little to the anterior side, which they approach within
about two-fifths of the whole distance : ligament long, narrow
at first, and expanding gradually outwards, dark horncolour
or black : hinge-line nearly straight : hinge-plate thick, and
short, strengthened in each valve by a slightly curved rib to
support the ligament, by a long angular rib on the anterior
side, and by a callous and short rib running nearly at a right
angle with the beak : teeth, in the right valve an erect and
wedge-like cardinal, and in the left two similar cardinals,
which resemble a pair of nippers ; each valve has a lateral at
no great distance from the cardinal teeth, of an irregular shape
and bent towards each other, that in the right valve being
sometimes double : inside chalky-white, but nacreous in some
parts and occasionally exhibiting minute pearls; margin
rather sharp : pallial scar indistinct ; the fold is withdrawn
far into the interior : muscular scars irregular ; the anterior
elongated and extending to the central rib, the posterior tra-
pezoidal. L. 0*9. B. 4.

* A bean-pod.

SOLEN. 11

Habitat : Large sandy bays at low-water mark of
spring tides in the under-mentioned localities : Christ-
church, Hants (Da Costa) ; Exmouth j Bideford ; North
and South Wales; south, east, and west of Ireland. It
is thrown up in the greatest profusion on the sands at
Pendine in Carmarthenshire. Mr. Grainger found a
single valve in the Belfast deposit ; and Mr. James Smith
has included it in the list of Argyleshire fossils. North
of Great Britain it has only been recorded by Miiller as
Scandinavian ; but its southern range extends from
Brittany to Sicily and Algeria. Mr. M f Andrew dredged
it on the coast of Portugal in 15 to 20 f., and off
Malaga in 4 f. ; and he obtained it on the shore at
Mogador. According to Weinkauff it is common at
Bona in brackish w r ater,

This elegant shell was first recognized as English by
Lister. I must venture to dissent from Linne and sub-
sequent writers, who referred it to e Le Molan' of Adan-
son. It is the Hypogcea hirudo of Poli.

Genus III. SOLEN * Linne\ PL I. f. 3.

Body narrow: mantle thickened in front: tubes for the
most part united, nearly sessile, or extensile in a limited de-
gree : foot flexible, when in action conical and pointed, but
when at rest disk-like.

Shell cylindrical, very inequilateral, divided into diagonal
compartments, sculptured only by the lines of growth : teeth,
one cardinal in the right valve, and mostly two in the left ;
laterals partly erect, sometimes wanting : pallial scar having
a narrow sinus at the posterior extremity.

This kind of shell- fish was well known to the an-
cients ; and the estimation in which they held it as an

article of food induced them to observe its habits with

*

* Razorfish ; supposed to be the Sw\?)v of Aristotle.

12 SOLENID.E.

an accuracy at least equal to that which is shown in
the accounts given by certain naturalists of our own
time. According to Aristotle the ScoXfjve? were said to
withdraw into their holes on a noise being made, and
to sink deeper when they perceived the motion of the
iron implements used for their capture. Athenseus in
his learned gossip of the philosophers at supper (an-
swering in some particulars to the ' Noctes Ambrosianse'
of our modern Athens) quotes some verses of Epichar-
mus, commemorative of Hebe's marriage, in which slen-
der Solens were enumerated among the dainties at the
nuptial feast. They are also mentioned by other Greek
writers. Sophron says that widows were especially
fond of them ; it does not appear what sort of consola-
tion they afforded. Diphilus pretended to distinguish
the male from the female Solen by their shells : that of
the former was striped, and the fish a good remedy for
the stone and similar complaints ; while the shell of the
female was of a uniform hue, and its fish more savoury.
They were eaten boiled or fried ; but the best way of
cooking them was to roast them on a wood fire until they
gaped. In Pennant's time they were brought up to
table fried in batter. The last-named author had a
strange notion that the Solens, " when in want of food,
elevate one end a little above the surface, and protrude
their bodies far out of the shell ?'. ! This is repeated by
Montagu and Wood.

The razorfishes (or " spoutfishes," as they were
called by Grew and other naturalists of former days)
usually burrow in sand at the verge of low-water mark,
not perpendicularly, but in a slanting direction at an angle
of about 60 degrees. On the retreat of spring tides
they may be seen nearly half out of their holes, appa-
rently taking in a supply of oxygen for their gills. They

SOLEX. 13

are evidently sensible of vibratory movements in the
air, as well as on the ground, taking alarm at greater or
less distances according to the state of the atmosphere
and direction of the wind. When the Solen is dis-
turbed it squirts ont water in a strong jet ; and having
thus compressed the volume of its body, it lengthens
and darts out its dibble- shaped foot, and rapidly disap-
pears below the surface to a depth of two or three feet.
A Solen-hunt requires considerable alertness; for if
you cannot approach near enough to catch them when
partly exposed to view — and this is not easy, their muscu-
lar strength being, in proportion to their size, far greater
than that of a man — and you delve with your hands after
them, they will probably beat you in the race. The
stake is much more important to them than to you, and
it calls for all their energies. Fishermen entice them
out of their holes by a pinch of salt, making (as they
say) the razorfish believe that the tide is coming in.
Reaumur, however, considered that the salt irritates
them, and causes a painful pricking sensation in the
mantle, which induces them to rise to the surface and
endeavour to get rid of the annoyance by expelling the
salt backwards. He also noticed the blind instinct
which the Solen has when taken out of its hole, and
held between the fingers in the open air, suspended
vertically : it protrudes its foot several times in suc-
cession, as if it were in the act of burrowing into its
native sands. The account given by Poli of Solen-fish-
ing at Naples is curious. We know that the flow and
ebb of the tide there are very slight, and different from
what takes place on our own shores. He tells us that
the lurking-place of the Solen is betrayed by a hole in
the sand, agreeing in shape with the apertures of its
tubes or siphons. "Where the water is shallow the fish-

14 SOLENID.E.

erman sprinkles some oil on the surface, in order to see
these marks more clearly. He then steadies himself by
leaning on a staff with his left hand, and feels for the
Solen with his naked right foot. This he catches, and
holds between his big toe and the next ; but although
his toes are protected by linen bands, the struggles of
the Solen to escape are so violent, and the edges of the
shell so sharp, that very often a severe wound is in-
flicted by it. Where the sea is five or six feet deep,
another mode of fishing is adopted. It consists in the
fisherman diving or swimming under water with his
eyes open, and, after having found the holes, digging
with his hands for the razorfish. Sometimes the Solen
so forcibly resists being taken, that it will suffer its own
foot to be torn awav, or will even die rather than sur-
render. Their power of locomotion is not limited to
burrowing; they can dart from place to place in the
water as quickly as a scallop, and apparently in the
same way. Pliny instances the razorfish as a luminous
mollusk ; but this has not been confirmed by any recent
observation. The breadth of the shell is very remark-
able in comparison with that of any other bivalve. In
the west of France they are called "couteaux" or "cou-
teliers." Another name (" seringues ") was suggested
by Reaumur as more appropriate.

A. Shell somewhat curved, flattened and thin ; hinge near
one end, and furnished with cardinal and lateral teeth.
Cidtellus, Schumacher.

1. Solen pellu'cidus *, Pennant.

8. pellucidus, Penn. Br. Zool. iv. p. 84, pi. kvi. f. 23 ; F. & H. i. p. 252,
pi. xiii. f. 3, and (animal) pi. I. f. 2.

Body compressed, varying in colour from pale yellowish -

* Transparent.

SOLEN. 15

white to brownish-yellow : mantle thick, protruded a little
beyond the valves of the shell ; edges plain : tubes contiguous
and nearly sessile ; orifice of each fringed with tentacles or
cirri of different lengths, which are spotted with yellow or
flake -white : gills unequal in size, the upper pair not being
half the depth of the lower pair : palps small, smooth outside
and pectinated within : foot tongue-shaped and flexible, lying
when at rest across the shell on the anterior side : liver green.

Shell usually sabre-shaped, but of various degrees of curva-
ture, tapering to each extremity, scarcely transparent except
in young specimens, glossy and partially iridescent : sculpture,
numerous and fine but irregular striae in the line of growth,
and a few slight and minute longitudinal striae in the middle,
which radiate from the beaks to the front : colour yellowish-
white, with sometimes faint transverse streaks of salmon-
colour : epidermis like oil-skin, yellowish-green or light
orange, puckered by the radiating striae : margins gently curved
in front and almost straight behind, rounded at the anterior
end, and obliquely truncated at the other end ; dorsal area
apparently separated from the ventral part, in consequence of
the epidermis being thinner and of a paler hue behind : beaks
inconspicuous, inclining a little to the anterior side, which they
approach within one-fifth of the whole distance : ligament
lanceolate, yellowish-brown : hinge-line straight : hinge-plate
short, strengthened in each valve by a slight rib to support
the ligament, and by a short and thicker rib at the other
end, which diverges inside towards the front anterior margin :
teeth somewhat irregular; in the right valve an erect and
wedge-like cardinal, and in the left two similar cardinals,
which resemble a pair of nippers ; the posterior cardinal in the
left valve is often branched or forked ; each valve has a lateral
at no great distance from the cardinal teeth, of an irregular
shape, and bent towards each other, that in the right valve
being occasionally double : inside polished ; margin sharp :
scars indistinct; pallial sinus short. L. # 4. B. 1*5.

Habitat : Gregarious in various parts of the British
seas, in sand (often mixed with mud), at depths of from
4 to 85 f. In a fossil state it occurs at Belfast and
in the Coralline Crag; and Philippi appears to have
recorded it from Palermo *, under the name of S. tennis.

* In the preceding volume of this work I inadvertently mentioned

16 SOLENID.E.

All writers on Scandinavian mollusca have enume-
rated the present species in their lists, from the Loffo-
den Isles to Kiel Bay, in 3-50 f.; Collard des Cherres,
Cailliaud, and Tasle have found it in Brittany ; M'An-
drew dredged it in the south of Portugal, off Gibraltar, in
the Gulf of Tunis, and Sicily, in 15-40 f. ; and Wein-
kauff procured it by the same means at Algiers in 20 f.

This pretty shell was discovered by the Rev. Hugh
Davies about the year 1770 on the Carnarvonshire
coast. Clark savs that on both the mantle- tubes " are
a few, large, rather long, white filaments, springing
from the body of the common sheath, just below the
siphon al orifices." I did not observe them in any of
the specimens that I examined. The foot is sometimes
red or pink of various shades. The shells are not unfre-
quently taken from the stomachs of haddocks. They
are occasionally distorted.

It is the S. pygmceus of Lamarck. S. pellucidus,
Spengler (from Chemnitz) is a tropical species, from
Nicobar.

B. Shell more or less curved, tubular, and rather solid ; hinge
at one end, and furnished with cardinal and lateral teeth.
Ensis, Schumacher.

2. S. ensis*, Linne.

8. ensis, Linn. S. N. p. 1114; F. & H. i. p. 250, pi. xiv. f. 2.

Body somewhat compressed, pale drab : mantle having <i
narrow fringed slit in the middle of the anterior side : tubes

Palermo and Panormi as two places, being misled by Philippi using
both names, in his work on the Sicilian Testacea, sometimes as different
habitats of the same species. Panormus or Panormum is the ancient
name of Palermo.

* Scimitar.

SOLEN. 17

very short, enclosed in a sheath, speckled with brown, and
encircled near the orifices by two rows of irregular cirri : gills
narrow, nearly of equal size, and adhering throughout : palps
pale brown, thin and delicate, smooth outside and striated
within : foot of a dull reddish hue, obliquely sloping at the
extremity, which is studded with very minute papilla?, and
covered with meandering red-brown lines in the interstices :
liver brown and granular.

Shell resembling in shape a French bean with the ends
cut off, of nearly equal diameter, opaque, glossy and partially
iridescent : sculpture, slight and irregular striae in the line of
growth, set at two different angles ; those in front are parallel
with the curve of the shell, while the strise on the dorsal area
or diagonal compartment run in an opposite direction. : colour
yellowish-white, with numerous reddish-brown longitudinal
streaks crossing the dorsal area : epidermis membranous, yel-
lowish-green, thicker in front than at the back : margins
equally curved before and behind, truncated at each side, but
more rounded at the anterior end, which is slightly constricted ;
dorsal area nearly equal in size to the rest of the shell : bealcs
inconspicuous, placed close to the anterior side : ligament very
long and narrow, yellowish-brown : hinge-line straight : hinge-
plate long, strengthened by a rib in each valve to support the
ligament, and thickened at the anterior end : teeth, in the
right valve an erect and wedge-like cardinal, enclosed in the
left by two much stronger and nipper-like cardinals ; late-
rals one in either valve, long, rib-like, erect at its extremity,
and somewhat bent, that of the left valve overlapping the
other : inside nacreous ; edges thin : pallial scar distinct,
with a shallow sinus at the posterior end : muscular scars
of unequal size ; the anterior linear, posterior oval. L. 0*5.
B. 3-75.

Habitat : Sandv bays from 3 to 20 f. Fossil in all
our "upper tertiaries, as well as in Norway and Italy.
Its European distribution in a living state extends from
the Faroe Isles (Landt) to Sicily (Maravigna) and the
Black Sea (Eichwalcl) ; Algeria (Beshayes and TV ein-
kauff) ; Canada and the United States (Bell, Gould, and
others) . The range of depth is from 2 to 20 f. in the
north, and from 4 to 40 f. in the south of Europe.

18 SOLENID^.

The locomotion of this species is the same as that of
8. pellucidus. Its foot is permeated by a series of aqui-
ferous ducts or canals, causing a great expansibility of
that organ. Gould says that the animal is " too long
for the shell ; " but its power of contraction equals that
of its extension. A distorted specimen, found by Mr.
Barlee, and now in the University Museum at Oxford,
is bent in an extraordinary degree. Whether the curve
of such a crooked generation might in course of ages be
increased, so as to form a nearly complete circle, would
be a curious speculation.

In the time of Aldrovandus it was called by the
Venetians "cappa longa." Linne doubted whether it
were not a variety of S. siliqua. The one certainly in-
habits deeper water than the other, and they are closely
related in form. The present species is Lister's S. curvus
(accidentally binominal), the Hypogaa falcata of Poli,
Ensis magnus of Schumacher, S. ensiformis of S. Wood,
and Ensatella Europcea of Swainson.

3. S. si'liqua*, Linne.

S. siliqua, Linn. S. N. p. 1113 ; F. & H. i. p. 246, pl.xiv. f. 3, and (animal)
pi. I. f. 1.

Body similar to that of 8. ensis, except in being rather less
compressed, and in the foot being yellowish-white, with its
extremity abruptly truncated, and marked with extremely fine
close-set and very pale lead-coloured lines.

Shell so closely resembling that of 8. ensis, except in being
of a much larger size, that it is sufficient to mention the few
particulars in which they differ. This is almost straight in-
stead of curved, much deeper in proportion to its breadth, and
more solid ; the margins at both ends are abruptly truncated ;
the cardinal teeth in the left valve are blunter, and sometimes
cloven ; and the lateral tooth in this valve is often double.
L. 1. B. 8.

* A pod.

SOLEN. 19

Tar. arcuata. Shell usually smaller, more or less curved,
but equally deep relatively to the breadth.

Habitat : Common on all our sandy shores which
are uncovered at spring tides ; seldom beyond that limit,
although in the Dredging Report of the British Associ-
ation in 1850 it is stated to have been taken in the
Orkneys at a depth of 12 f. The variety is found on
many parts of our coasts, especially those of Ireland
and Scotland — I have a specimen from Burra Firth
in Unst, of unusual dimensions, viz. nearly \\ inch
long or deep by 7 inches in breadth ; Norway (Sars).
This variety was noticed by Turton in his ' Concho-
logical Dictionary;' it is referred by Forbes and Han-
ley to S. ensis. The late Dr. Lukis found it living
with that species in Belgrave Bay, Guernsey, and sent
me specimens of both for comparison. The typical
form occurs in many of the newer or postpliocene
deposits, as well as in the Norwich and Bed Crag;
Uddevalla (Malm) ; Sicily (Philippi). Its foreign range
comprises Behring's Straits, the North-east coast of
America, Faroe Isles, and all the intermediate shores to
the iEgean, including the African side of the Mediter-
ranean.

In Lister's days it was called in Yorkshire " Hose-
fish/' and caught (if the tide was out at night) by
candle-light. He adds that they make a delicious sauce,
and have the flavour of shrimps. "In Ireland it is
much eaten in Lent'" (Da Costa). Fleming says that
when a little stale they are a tempting bait for cod and
haddock. The teeth are liable to vary. In a specimen
from Oxwich Bay near Swansea the laterals are placed
closer than usual to the hinge ; and that of the left valve
is branched, as in S. pellucidus, and divided into three.

S. novacula of Montagu and S. ligula of Turton

20 solenid^:.

(judging from a comparison of authentic specimens with
the descriptions of those authors) are varieties of S.
siliqua, and only distinguishable by the absence or size
of some of their teeth. The present species is the Hy-
pogaea crinita of Poli, S. gladius of Bolten, and S. gla-
diolus of Gray.

C. Shell straight, tubular, and rather solid ; hinge at one end,
and only furnished with a single lateral tooth in each
valve.

4. S. vagi'na*, Linne.

S. vagina, Linn. S. N. p. 1113. 8. margmafus, F. & H. i. p. 242, pi. xiv.
f. I, and (animal, siphon only) pi. I. f. 3.

Body cylindrical, pale yellowish-brown : mantle thickened :
tubes wrinkled across ; each is encircled "by several rows of brown-
ish spots, and near the extremity by a row of very short
tentacular cirri ; orifice of the lower tube distinctly scalloped,
that of the upper one plain : (/ills long, linear, orange-brown :
palps large, sharp-pointed : foot oblong, yellowish-white.

Shell exactly cylindrical, and of equal size throughout,
somewhat glossy, opaque : sculpture as in the preceding two
species : colour pale yellowish-brown (with an orange tint in
aged specimens), and marked with streaks of a darker hue in
the transverse line of growth : epidermis membranous, yel-
lowish-brown : margins equally straight before and behind,
obliquely truncated at the anterior end, which is deeply con-
stricted (as if it had been tied while in a soft and plastic state
with a string), and transversely truncated or very slightly
curved at the posterior extremity ; dorsal area or compartment
not so distinct as in the other species : beaks inconspicuous,
separated by the constriction from the anterior end : ligament
very long and narrow, dark homcolour : hinge-line straight :
hinge-plate long, strengthened by a rib in each valve to support
the ligament, and thickened at the anterior end : teeth, in each
valve a single wedge-like cardinal, resembling in shape the
leaf of a water-lily, and attached to the hinge by an obliquely
twisted stalk ; the tooth hi the right valve is outermost : inside

* A sheath.

SO LEX. 21

chalky-white ; edges thin : paJlial scar well marked, placed
far within : sinus deep, but narrow, defined by a broad line on
each side, like the prongs of a steel fork : muscular scars deep ;
anterior linear, and parallel with the hinge-line ; posterior
oblong. L. 0-85. B. 5.

Habitat : With S. siliqua, but more local. Guernsey
and Jersey (Hanley) ; Weymouth (Pulteney) ; Exmouth
(Clark) ; Kingsbridge (Montagu) ; Falmouth (R. L.
King) \ Laugharne in Carmarthenshire and the adjacent
coasts (Montagu and others) ; Anglesea (Pennant) ;
north, east, and south of Ireland (Thompson and others).
" Alluvial deposits/' Belfast (Hyndman and Grainger) ;
Italian tertiaries (Menard de la Grove, Brocchi, and
Philippi). Its exotic range comprises Norway (Loven,
and Asbjornsen) ; north coast of Holland (Waarden-
burgh) ; Heligoland (Frey and Leuckart) ; France (De
Gerville and others) ; Portugal (M f Andrew) ; Italy ,
from Spezzia (Capellini) to Sicily (Maravigna) ; Adriatic
(Chieregliini) j Black Sea (Kutorga) ; Algeria (Deshayes
and Weinkauff) ; St. Michael, Azores (Drouet) ; Red
Sea (Philippi).

The ancient naturalists had some strange notions as to
the sexes of the Mollusca. Aristotle, as is well known,
believed in their spontaneous generation ; but a different
opinion prevailed about three centuries ago, when Belon
and Rondelet described S. siliqua as the male, and S.
vagina as the female of the same species. The reasons
which they gave for this distinction were not altogether
uncomplimentary to the fair sex, consisting in S. vagina
being (although smaller) of a uniform complexion, and
more sweet-savoured than the other. Reaumur and
Deshayes have given accounts of the animal tolerably
agreeing with my own. At Cherbourg, Lisbon, and
Spezzia it is sold in the fish-markets, but not so much

22 pandorid^.

esteemed as S. siliqua. The flavour is said to be pecu-
liar. Poli mentions its being so acrid, that none but
the poorest would use this kind for food. The shell
differs from that of the last-named species in being more
regularly cylindrical, deeper in proportion to its breadth,
and of an orange-grey instead of a purplish-green colour ;
the diagonal compartment is less marked ; the sides are
more truncated ; the anterior end is constricted ; and it
has fewer teeth.

Linne's description of S. vagina in the f Mus. Lud.
Ulr. Reg/ is peculiarly appropriate to this species,
although in the 12th edition of the ' Syst. Nat/ he
appears to have united with it an Indian species which
has been named S. truncata by W. Wood. Our species
(as a mollusk) is the Hypogcea tentaculata of Poli, and
(as a shell) the S. marginatus of Pulteney and Donovan.
The last-mentioned author said it was not the S. vagina
of Linne, but he gave no reason for saying so.

Family XVII. PANDO'RIDiE, Gray.

Body oval or oblong : mantle having a slit on the anterior
side for the passage of a foot, and forming on the other side a
tubular sheath : tubes short, united nearly to their openings,
which are fringed : gills two on either side, each pair being
more or less united, long, narrow, and slightly curved : palps
corresponding in. number with the gills, and triangular : foot
tongue-shaped.

Shell oval or oblong, inequivalve, pearly, gaping at the
posterior side, which is flexuous and elongated, and projects
upwards : bealcs very small : cartilage at the posterior side,
wholly internal, long and oblique : hinge strong : teeth, either
a single cardinal in each valve, or an oblong plate, which is
attached only to the cartilage and partly covers the hinge :
pallial scar slight, and narrowly sinuated : muscular scars
small.

PANDORA. 23

The shape of the shell, its nacreous substance, and the
absence of an external ligament are the chief character-
istics that distinguish this small family. The two genera
which compose it have a different hinge- structure, but
are in other respects so closely allied, that it is more
convenient to place them together. The Pandorida
inhabit sand at various depths.

Genus I. PANDO'RA*, Hwass. PI. I. f. 4.

Body oval, compressed on one side and rather tumid on the
other, thin, and gelatinous : gills free, except at their bases,
where each pair is united, and terminating in the tubular
sheath : p>alps short : foot small, thick, and swollen at the
point.

Shell oval, inequilateral, scaly and smooth ; left valve flat
and the other convex : epidermis membranous and thin : teeth
consisting of a plate-like cardinal in each valve : pallicd scar
pitted at intervals : muscxdar scars well marked, roundish-oval.

The merit of instituting the genus Pandora is due to
Hwass, a German justiciary, and not to Bruguiere as is
commonly supposed. Both gave the same species (Tel-
Una buequivalvis, Linne) as the type. This is clearly
shown by the 11th volume of Chemnitz (p. 211), which
was published between two and three years before the
? Encyclopedie Methodique/ Carpenter has remarked
the complete conformity that exists between the shells of
the present genus and Avicida, — namely, in the regular
prismatic arrangement of the cellular structure, the axes
of the prisms being perpendicular to the surface ; in the
presence of distinct partitions between the cells, forming
a persistent membrane, which is left after decalcification j
and in the truly nacreous interior. The genus appears
to be of comparatively recent origin; for (according to

* A mythological character.

24 PANDORID/E.

Searles Wood) no well determined fossil species have
been met with in anv formation older than the Paris
basin. The animal was included by Poli in his genus
Hypogcsa. For the shell Bolton proposed Calopodium,
and Brown Trutina.

Pandora in^quival'vis"*, Linne.

Tellina in&quivalvis, Linn. S. N. p. 1118. P. rostrata, F. & H. i. p. 207,
pi. viii. f. 1-4, and (animal, as P. obtusa) pi. G. f. 10.

Body transparent, with flake- white specks ; mantle thin,
scarcely (if at all) protruded : tubes short, separate although
nearly close together, issuing from a very slight, pellucid and
membranous sheath, which extends beyond the shell at its
posterior end, and is partly continued round the edges ; orifices
wide, plain but jagged : gills unequal-sized, the upper being
twice the size of the lower pair, which are almost rudimentary ;
they are pectinated by the blood-vessels on both surfaces :
imlps very short, reddish-brown, striated transversely, and
often overlapping each other: foot white: liver green: ovary
red-brown.

Shell irregularly triangular, right or convex valve consider-
ably overlapping the other ; it is variable in thickness and opa-
city, and somewhat glossy : sculpture, slight plait-like marks of
growth, and sometimes a few imperfect longitudinal wrinkles on
the flat valve, which are only perceptible in front and appear to
radiate from the beak : colour pearl-white ; epidermis filmy
margins rounded or obtusely angular on the anterior side
forming in front a nearly semicircular but oblique curve
which is prolonged at the posterior side to a blunt point
dorsal margin straight or slightly incurved, furnished in the
right valve with a double furrow, and in the left with a double
ridge, both of which extend from the beak to the posterior end
or point : beaks extremely minute and tubercular ; umbones
not prominent : cartilage horn colour, running inwards on the
posterior side at an acute angle with the dorsal margin, and
occupying a groove in each valve, the sides of which are thick-
ened : hinge-line straight, or more or less incurved : hinge-
plate long, strengthened by a rib in the left valve, that fits into
a slight furrow in the opposite valve : teeth, in the right valve

* Valves unequal in size.

PANDORA. 25

an erect cardinal, set at a right angle with the hinge-line, and
in the left valve a longer and somewhat horizontal cardinal,
set at an acute angle with the upper margin of the anterior
side ; the teeth and cartilage are on opposite sides of the beak,
and diverge from each other: inside highly polished and iri-
descent, slightly striated in a radiating direction ; edges thin
and sharp : scars more or less distinct, according to the thick-
ness of the nacreous lining. L. 0*6. B. 1*25.

Tar. 1. tenuis. Shell much smaller, and of a delicate tex-
ture, proportionally broader or more produced at each end, with
an oblique and ilexuous outline ; dorsal margin straight.

Yar. 2. obtusa. Shell smaller and thinner, longer in pro-
portion to its breadth; the posterior side larger, and not so
much produced or extended ; dorsal margin also straight.

Monstr. Shell oval, with the sides shorter than usual ;
dorsal margin projecting a little outwards.

Habitat : In sand, Channel Isles, at the recess of
spring tides, and in shallow water ; often among Zoster a
marina. Var. 1. Between 85 and 100 f. off Unst in
Shetland. Var. 2. From 7 to 50 f. on all our coasts.
The monstrosity is from the Hebrides and Shetland.
In a fossil state the typical form occurs in the Coralline
Crag, and the variety obtusa in the Red Crag ; both are
noticed by Philippi from different parts of the tertiary
formation in Sicily. The first has only a southern range,
from Guernsey to the iEgean ; while the distribution of
the other is wider, reaching to the Canaries in the
same direction, and extending northward to Spitzbergen.
In the iEgean, Forbes gave 4 f. for P. inaquivalvis, and
71-10 f. for P. obtusa ; and at Mogador M f Andrew
recorded the respective depths of 3 f. and 35-40 f. for
the two forms. The observations made by M. Martin
in the Gulf of Lyons showed similar results.
. The animal is shy and easily alarmed. Lacaze-Du-
thiers, in his valuable essay on the development of the
gills in LameUibranchiate Conchifera (Ann. Sc. Nat. 4 e

vol. in. c

28 pandorid^:.

ser. Zool. ii.), remarks with respect to this species, that
the outer gill, which resembles a hood, might at first
sight be taken for a single leaf, so disproportionately
small is its size. He considers it a case of arrested
development. Mr. Jordan says, " Whilst collecting
specimens at Jersey, I noticed that they have a habit of
squirting, like Saxicava rugosa and the Pholades when
first touched ; one individual ejected a fine stream, fully
sixteen inches high." In Mr. Clark's description of the
animal of var. obtusa the tubes are stated to be fringed
at their orifices with fine white short cirri ; the margin
of the sheath, in some specimens, is marked by a fine
orange line; and the base of the cirri and margins of
the orifices are usually encircled by a dead-white narrow
thread. The ovary is of a reddish-brown colour. I
found it to contain in Julv an immense mass of vesicular
ova in different states of growth ; the more forward of
them resembled in shape some species of Cythere. Adult
specimens vary in their comparative length and propor-
tions, as well as in the prominence of the ridges on the
dorsal side. The difference between the typical shell
and the variety obtusa apparently arises from the nature
of their respective habitats — the one being sublittoral,
and the other belonging to deeper water. An inter-
mediate form has been taken by Cailliaud on the coast
of Brittany, and by M' Andrew at Corunna. On a
superficial view, indeed, it would seem as if a valid
distinction existed in the length from the beak to the
front margin being always greater in P. incequivalvis (or
rostrata), and on the posterior side in P. obtusa; but
this only shows that varieties, as well as species, have
some one character of their own. Such may be expected
when the conditions of life varv. The extension of the
posterior side in the typical form may be caused by the

PANDORA. 27

difference of locality. When the littoral zone is sandy,
the surface is apt to be disturbed by waves and occasional
storms, so that the stratum may be of a greater or less
thickness at one time than at another : now it is covered
by a deposit of material thrown up by the sea ; in a few
days this cover may be stript off. In order to prevent its
tubes being choked by an accumulation of the imported
material, the Pandora living between tide-marks gradu-
ally lengthens that end of its shell. The varietv which
inhabits deeper water is not exposed to fluctuations of
this kind ; it therefore does not require any such pro-
vision, and lies undisturbed in its level bed. This mav
explain the variation in the proportions of length and
breadth which is exhibited bv the two forms. The dif-
ference of thickness in the shells of P. iruequivalvis and
its varieties also depends on habitation. I. am inclined
to think that, with regard to every species living both in
the littoral and coralline zones, the shell is thicker in
the former and thinner in the latter. Examples to
illustrate this proposition occur in Venus gallina and its
varieties striatula and laminosa, Mactra solida and its
variety elHptica, Trochus ziziphinus and its small conical
varietv, Buccinum undatum and its varietv Zetlandica,
and in many other species. Experiments made by Dr.
Davy, Forchhammer, and Bischoff have proved that the
quantity of carbonate of lime held in solution by sea-
water, and from which shells are produced, is greater on
the coast than in the ocean ; it is derived from the land,
and brought down to the sea by rivers and streams, the
washings of rain, and the action of waves. This fact
ought not to be lost sight of in discriminating species
from varieties of which the comparative solidity and
size are the sole or chief criteria.

Lamarck at first named this species P. margaritacea,

c 2

28 PANDORIDiE.

and afterwards P. rostrata ; the young is the P '. flexuosa
of Philippi, and the animal the Hypogcea gibba of Poli.
It is also the Trutina solenoides of Brown. The variety
obtusa was described bv Menschen as Anomia tabacca,
by Montagu as Solen pinna, and by Leach as P. glaci-
alis ; the young is the P. oblong a of Philippi. Lamarck
changed the specific name imposed by Linne, either
from caprice (as seems to have been his custom), or on
the ground that it denoted an essential character of the
genus and therefore was superfluous. I am not satisfied
with this reason, believing that all designations, whether
generic or specific, are merely symbols of distinction,
and that the law of priority in zoological nomenclature
ought not to be disregarded because the name of one
species represents a character that is common to others
of the same genus. I have restored the original name,
by which this species is well known throughout the
greater part of Europe.

Genus II. LYON'SIA*, Turton. PL II. f. 1.

Body oblong, somewhat compressed, rather thick : gilh
forming apparently a single leaf on either side, in consequence
of each pair being doubled upon itself: palps long and narrow :
foot tongue-shaped, rather large, flattened, and provided with
a byssal groove.

Shell oblong, nearly equilateral, finely striated lengthwise :
right valve more convex than the left : epidermis fibrous :
hinge furnished with a free plate or ossicle, which covers the
cartilage : muscular scars slight ; anterior oblong, posterior
roundish.

A link connecting the Pandorida with the Anatinidce,
having the same shape and pearly nature as the former,
and the peculiar hinge-process or ossicle of the latter

* Named after the late Mr. W. Lyons, an active British conchologist.

LYON SI A. ' 29

family. This relationship has also been remarked by
Carpenter in his account of the microscopical structure
of the shell. The mantle-tubes are united in the present
genus, as well as in Pandora ; they are separate in the
Anatinidce. Philippi considered Lyonsia to be closely
allied to Galeomma ; but I cannot see much resemblance
between them. Mr. W. "Wood was the first to notice
the curious appendage which coverts the hinge. It was
conjectured by Clark that it acted like the check- tape of
a trunk, to prevent its being opened too widely. This
might be so if it were attached to the shell. I should be
disposed to attribute to it quite a contrary action, and
to believe that its use may be to strengthen the hinge,
and to protect it from being squeezed too closely and
broken, as is frequently the case with certain species of
Anatina and Thracia. The ossicle of Lyonsia is of a
different shape and position from that of the Anatinidce.
In those it is semiannular, and clasps the hinge crosswise
with the two ends; in the present genus it is flat, and
lies over the hinge lengthwise, with one end at the ante-
rior and the other at the posterior side of it.

This genus has several synonyms, including Maydala,
Leach, Osteodesma, Deshayes, and Pandorina, Scacchi.

Lyonsia Norve'gica*", Chemnitz.

Mya Norvegica, Chernn. Conch. Cab. x. p. 345,. 1. 170. f. 1647, 8. L. Nor-
vegica, F. & H. i. p. 214, pi. viii. f. 6-9, and (animal) pi. H. f. 3.

Body milk-white, sometimes with a tinge of yellow or pale
brown : mantle thin ; edge studded at the anterior side with
from 8 to 10 papillce, which are of a darker hue in coloured
individuals : tubes nearly sessile ; orifice of the lower tube
fringed with a few short, thick, and close-set cirri ; upper
tube having a plain bulbous orifice, but furnished with the

* Norwegian.

.30 PANDORIDiE.

usual hyaline protrusile valve; this tube is speckled -with
minute sand-like points ; each tube is encircled at its base by
a few cylindrical filaments, which are somewhat longer than
the tubes, and are occasionally speckled with flake-white :
gills and palps pale brown : foot flexible, white, cloven at the
heel, whence byssal filaments are produced.

Shell irregularly rhomboidal, the left or convex valve some-
what overlapping the other, of a membranous consistency,
opaque and lustreless : sculpture, numerous rows of fine gra-
nulated striae, radiating from the beaks to the outer margins ;
between each of these striae are five or six rows of minute
and close-set tubercles or pores, which are connected with the
tubular structure of the external laver of the shell ; there are
also occasional lines of growth : colour pale yellowish -white :
epidermis light-brown, and having an agglutinating property,
by means of which the surface becomes invested with a coat
of sand and Foraminifera or other organic remains : margins
broad and rounded on the anterior side, flexuous or somewhat
indented in front, curved obliquely upwards to the posterior
side, which is prolonged into a beak-like form and truncated
at that end, with a double but indistinct ridge in the left
valve, and a corresponding furrow in the right ; dorsal margin
incurved : beaks triangular, inclining to the anterior side ;
umbones rather prominent : cartilage golden-yellow, lying
nearly parallel with the hinge-line, and contained in a groove
in each valve, the sides of which are thickened : liinge-line
obtusely angular : hinge-plate long, strengthened by a rib in
the left valve, which fits into a slight furrow in the opposite
valve : ossicle irregularly quadrangular, with the broader end
towards the posterior side, where it is notched or forked ; the
narrower end is truncated and placed immediately under the
beaks : inside highly polished and iridescent ; edges thin, re-
flected or folded outwards in the right valve : muscular scars
often double. L. 0-875. B. 1-7.

Var. elongate. Shell more slender, and transversely elon-
gated : Osteodesma elonqata, (Gray) Hanley, Rec. Sh. p. 25,
pi. 13. f. 27.

Habitat: All our coasts, in sand, from 4 to 86 f.,
but nowhere common. The variety has been found in
the Hebrides and Shetland. L. Norvegica has not been
noticed as a British fossil ; but Philippi has recorded it

LYONSIA. 31

from the newer tertiaries of Sicily. Its foreign range
in a living state comprises the Sea of Ochotsk, and the
coasts of Iceland, Scandinavia, France, Italy, Algeria,
Greece, and Madeira, at depths varying from 10 to 70 f.
in northern, and from 4 to 70 f. in southern latitudes.

Miss Hutchins is the reputed discoverer of this re-
markable and interesting shell. According to Clark
the gills consist of a single leaf on each side j the tubes
appear to be enclosed in one sheath, which has the
margin finely dentated ; and each orifice is garnished
with about eight white simple cirri, and as many black
equidistant points at their external edges. He has not
mentioned the filaments at the base of each tube. Such
discrepancies are extremely perplexing ; and if the iden-
tification of any species depended solely on characters
afforded by the soft parts, the study of conchology would
be almost impracticable. The faculty and means of
observation, as well as the good faith possessed by Mr.
Clark, were certainly not inferior to those which I have
exercised ; and yet how different is the result ! The
microscopic pustules covering the surface of the shell
appear to be the ends of the tubes which compose the
outer layer ; these are open in the young, and closed in
the adult. The inner layer is entirely nacreous. The
shells are occasionally found in the stomach of the red
gurnard. Dr. Lukis supposed that the young disguise
themselves in their sandy coating more completely than
the adult; but this is not always the case. The epi-
dermis is of a gelatinous or viscous nature, and thus
grains of sand as well as organic particles become
attached to it.

It is the My a nitida of Fabricius (but not of M tiller),
M. striata of Montagu, Amphidesma corbuloides of La-
marck, My a pellucida and Myatella Montagui of Brown,

32 ANATINID/E.

Tellina coruscans of Scacchi, and Pa?idora? (equivalvis
of Philippi. It likewise appears to be the Mya membra-
nacea of Gmelin, from Miiller's c Prodromus/ judging
from the description j although Dr. Morch informs me
that the shell figured in Olafsen and Povelsen's Voyage
to Iceland, and referred to by Mliller for this species,
represents Astarte sulcata, var. elliptica.

Family XVIII. ANATrNID^E, D'Orbigny.

Body oval or oblong : mantle very thin : tubes long ; orifices
fringed : gills one on each side : palps two on each side : foot
lanceolate or tongue-shaped, small, and compressed.

Shell oval or oblong, slightly inequivalve, gaping more or
less on each side, and truncated at the posterior end : beaks
small, inclining to the posterior side, mostly fissured : epidermic
slight : ligament sometimes external and situate at the posterior
side, besides invariably an internal cartilage, which is contained
in a pit or receptacle under the beak in each valve : hinge fur-
nished with a free crescentic ossicle, placed across the hinge-
line at the anterior side of the beaks ; otherwise toothless :
pallial scar narrowly but deeply sinuated : muscular scars
small and irregular.

The typical genus, Anatina, is a native of tropical seas.
It may be distinguished from Thracia in the tubes being
united, the pearly nature of the shell, and in having
inside an oblique falciform rib, proceeding from the car-
tilage-pit towards the posterior side in each valve. This
process is formed apparently in consequence of the
beaks being fissured in that direction, and it serves as
an upright girder to strengthen the shell. Something
of the same kind, however, may be observed in most
species of Thracia. The genus Anatina of Schumacher
is different from that of Lamarck, and belongs to the
Mactrida. The Anatinidce usually frequent a sandy or

THRACIA. 33

nullipore bottom at various depths ; but a British species
of Tkracia (T. distorta) prefers a more secluded habitat,
aud occupies the deserted holes made by Saxicava rugosa
iu limestone, or other rock- cavities, as well as tufts of
Corallina officinalis.

Genus THRA'CIA* Leach. PL II. f. 2.

Body oval : tubes separate.

Shell oval, nearly equilateral, rather thin, having a tuber-
cular or shagreen -like surface : colour sometimes tinged with
yellow.

Montagu proposed his genus Ligula chiefly to receive
the species which we now assign to Thracia ; but, for
the reasons which I have given in the second volume of
this work (p. 433), it is inexpedient to retain that name
in the Mollusca.

According to Dr. Carpenter the minute elevations or
points, that roughen the surface of the shell, represent
numerous isolated cells filled with calcareous matter,
and forming a superficial coating superposed upon the
ordinary external layer; the epidermis is extended over
these points, and sinks down into their interspaces, just
as the human epidermis covers the papillary surface of
the true skin. The proper external layer is composed of
polygonal cells, with sharply defined boundaries, having
large nuclear spots strongly resembling some of those
which are exhibited in My a armaria. The total quan-
tity of animal matter or membrane contained in the
substance of the shell is extremely small, although the
cellular structure in all probability results from the cal-
cification of animal tissue. The structure of the internal
layer is scarcely distinguishable. The power of tension

* A Sea-NympL

c5

3-1 ANATlNIDiE.

continually exercised by the strong and elastic cartilage
exceeds that of the shell ; and the latter being the weaker
body, gives way and is split in the conflict. Only one
species ( T. distorta), which is comparatively more solid
than the others, resists the strain and remains un-
injured.

The synonymy of the European species has been
lamentably perplexed ever since the time of Pennant,
notwithstanding the pains taken by Loven and the
authors of the c British Mollusca' to unravel the tangled
skein. This makes it extremely difficult to define with
any certainty the geographical distribution of some of
these species. Geologically Thracia appears to be an
ancient genus. " Fossils of this form are found in the
lower Oolites, and doubtfully so in the Carboniferous
series" (S. Wood). It is the genus Odoncincta of Da
Costa, and has received other equally barbarous names
from modern authors- Cochlodesma, Couthouy, does
not differ in any respect except in the absence of an
ossicle : all the British species of Thracia possess this
appendage.

A. Nearly equilateral.
1* Thracia PRiETE'NUis*', Pulteney.

Mya pratenuis, Pult. Cat. Dors. p. 28, pi. iv. f. 7. Coehlodesma prestenue,,
F.&H. i. p. 235, pLxv. f. 4.

Body thin, clear white : giUs strongly pectinated, each
divided by an oblique furrow into two parts, the upper being
less deep than the lower portion : foot white.

Shell triangularly oval, compressed, opaque, somewhat
glossy ; right valve more convex than the left, and slightly
overlapping it : sculpture (besides the usual marks of growth),
close-set and microscopical transverse hair-like lines or scratches

* Very thin.

THRACIA.

35

on every part except the posterior side, which is covered with
numerous concentric rows of tubercles interspersed with line
strice that appear to radiate from the tubercles : colour milk-
white : epidermis membranous, creamcolour : margins semi-
circular on the anterior side, moderately curved in front, with
a slight indentation or fiexuosity towards the posterior side,
which is more rounded than truncated ; posterior dorsal margin
sloping and straight ; anterior dorsal margin slightly curved :
beaks projecting, with an abrupt excavation underneath, caused
by the compression or fracture of the hinge ; this part is de-
fined by a sharp but irregular ridge in each valve : ligament
exceedingly small (being only visible in fresh specimens),
placed close to the hinge on the posterior side; it is dark
horncolour : cartilage golden-yellow, contained in a triangular
and shallow cup, which is solid, attached to the hinge-plate
by a ledge, and projects inwards horizontally and at a right
angle with the hinge ; from the lower part of this cup or car-
tilage-pit in each valve runs an oblique and sharp ridge to the
posterior adductor muscle, and the shell is considerably thick-
ened in that part : hinge-line obtusely angular : hinge-plate
narrow and thin : ossicle falciform, clasping the hinge close to
the beak on the anterior side : inside chalky- white, except the
muscular scars and below the cartilage-pit, where the surface
is polished and nacreous ; it is furnished with a slight rib in
the line of fracture ; edges sharp : pallial and muscular scars
nearly marginal. L. 085. B. 1*3.

Yar. curia. Shell more oval, or longer relatively to its
breadth.

Habitat : Land's End to Unst, from 4 to 60 f. ; and
at low w r ater, spring tides, on the coasts of Kerry and
Galway. The variety is from Shetland and Cork Har-
bour. Fossil in the Coralline Crag (S. Wood) ; Cliris-
tiania (Sars) ; Palermo (Philippi). The extra- British
distribution comprises Iceland, the Faroe Isles, Scandi-
navia (3-30 f.), the north of France, Adriatic, Naples,
and Sicily.

The course of striation, or the arrangement of the
microscopical grannies, in this shell is the reverse of that
in Lyonsia Norvegica, viz. transverse instead of longi-

36 axatinid^e.

tudinal. Petiver called the present species Chama prcc-
tenuis, or the " small, white, thin Spoon-hinge" Some
authors have referred it to Schumacher's genus Peri-
ploma ; but his description and figure give a different
and more complicated hinge-structure. Leach carved
out of it two other genera, Bontia or Bontcea and Ga-
laxura. It is the Anatina truncata of Lamarck, and A.
oblonga of Philippi, the former having been identified
by Collard des Cherres, and the latter by Sars, with
typical specimens. Collard des Cherres enumerated it
in his list as Beriploma myalls, and Chiereghini as Tel-
Una frag Ms sima ; S.Wood described it as Cochlodesma
prcetenerum.

2. T. papyra'cea*, Poli.

Tellina papyracea, Poli, Test. Sic. i. p. 43, t. xv. f. 14, 18. Thraeia pha-
seolina, F. & H. i. p. 221, pi. xviii. f. 5, 6, and (animal) pi. H. f. 4.

Eody varying in colour from clear white to pale brown,
covered with minute and numerous tubercles or papilla?, that
give the surface a frosted appearance : mantle protruded con-
siderably at each end ; edges plain : tubes separate, cylindrical,
but short and wide, capable of being much inflated and un-
equally distended, sometimes club-shaped at their extremities ;
the upper tube is marked with eight, and the lower with four
faint longitudinal lines or streaks, which terminate at the
orifices in the same relative number of short, thick, and blunt
cirri : gills forming two large suboval plates, each divided in
the middle by a deep and oblique furrow ; they are smooth
within and pectinated without : palps equal-sized, short, and
triangular : foot flat and expansile, bluish- white.

Shell thinner than the last species, and more inequivalve,
more convex (though compressed towards the front and sides),
and more elongated transversely : sculpture similar, but more
delicate : epidermis less persistent, and having usually a rusty
tinge on the posterior side : margins not so much rounded on
the anterior side, decidedly and more abruptly and obliquely

* Paper-like.

THRACIA. 37

truncated at the posterior end, with a well-defined angle on
that side ; posterior dorsal margin somewhat recurved, instead
of sloping ; anterior dorsal margin longer : beaks less promi-
nent, with a slighter and less distinct excavation below them :
ligament rather large, but short, yellowish-white or pale brown,
keeping the valves asunder on the posterior side, and when
removed leaving a lanceolate gap : cartilage yellowish-brown ;
pits obliquely elongated sideways, and not projecting so far
inwards as in T. praztenuis ; connecting ridge at the bottom
thicker and less distinct : ossicle semiannular, placed as in that
species : other particulars the same, except that in the present
species the beaks only (and not the hinge) are fissured, and
the rib-like mark of repair in the interior is therefore wanting.
L. 0-6. B. 1-1.

Yar. 1. gracilis. Shell more slender, and approaching a
cylindrical shape, thinner, more uniformly convex ; posterior
end shorter in proportion.

Yar. 2. viUosiuscula. Thicker, and less elongated trans-
versely ; posterior angle more rounded, but truncated. Ana-
tina viUosiuscula, Macgillivray in Edinb. New Phil. Jonrn.
April 1827, p. 370, pi. i. f. 10,' 11. T. viUosiuscula, F. & H. i.
p. 224, pi. xvii. f. 4, 7.

Monstr. Furrowed on the posterior slope, or having mis-
shapen valves.

Habitat : Sandy bays in the laminarian zone ; rather
common. Yar. 1. Bantry Bay, and twenty miles north
of Unst in 86 f. Var. 2. As widely diffused as the
typical form, but usually in deeper water, or where the
supply of calcareous material is more plentiful. Fossil
at Belfast (Grainger) ; Kyles of Bute, and Lochgilphead
(Geikie) ; Coralline Crag (S.Wood). Both the typical
kind and the variety viUosiuscula range from Iceland to
the iEgean and Canaries, at depths of from 2 to 35 f. ;
an intermediate form has been taken by Steenstrup in
Iceland, by Malm on the Swedish coast, and by
M 'Andrew in Yigo Bay. Mr. Malm's son found the
variety subfossil at Uddevalla, and Sars in the newer
part of the glacial formation near Christiania.

38 anatinid^.

My finest specimen measures only two lines more in
length and breadth than the average dimensions given
in the description; but Lilljeborg obtained some in
Finmark of a much larger size. I made an inexcusable
blunder in stating (Ann. Nat. Hist. Sept. 1859) my
belief that the present species was identical with T. dis-
torted.

This is the Tellina fragilis of Pennant (but not of
Linne) ; and that specific name ought perhaps to be
retained. It is also the My a punctulata of Renier,
Ligula pubescens of Montagu ("smaller specimens"),
Amphidesma phaseolina of Lamarck, and Anatina trun-
cate/, of Macgillivray (Aberd. Moll.). Chiereghini enu-
merated it in his list of Adriatic shells as My a truncata,
according to his learned editor Dr. Nardo : this shows
the difficulty of ascertaining the limits of geographical
distribution, if we trust to local catalogues which have
not been compiled by competent authorities, nor been
subjected to such revision. The variety villosiuscula is
the T. ovata of Brown, and Anatina intermedia of Clark.

3. T. pubes'cens*, Pulteney.

Mya pubescens, Pult. Cat. Dors. p. 27, pi. iv. f. 6. T. pubescens, F. & H. i.
p. 22(5, pi. xvi. f. 2, 3.

Shell of a gigantic size and considerable solidity compared
with T. papyracea ; it is also more of an oval shape, being
proportionally longer from the beaks to the front margins, and
shorter in a transverse direction ; the smaller or left valve is
flatter, and the inequality of the valves is more observable ;
the umbonal part is sculptnred by rather strong, but obscure
concentric ribs or folds ; the whole surface is finely granulated,
although more strongly at the sides ; the colour is sandy, in-
stead of white ; it is of a dull hue ; and the epidermis has
more of a yellowish cast. L. 2. B. 3.

* Fur.-rrrown.

THRACIA. 39

Habitat : Cornwall, Devon, and Dorset ; procured
by trawling. The reputed Irish localities are doubtful :
this species has been often mistaken for the adult of
T. papyracea : the only specimen in Mr. J. D.
Humphreys's extensive collection of shells from Dublin,
Cork, and Bantry was marked by him " England." Mr.
Grainger obtained it in a dead state at Belfast, where
it is also found in a post-pliocene deposit, as well as in
the Coralline Crag. The foreign localities of which I
am assured are Morbihan (Mace and Tasle) ; Provence
(Martin) ; Gibraltar, 8 f. (M f Andrew) ; and /Egean,
70 f. (Forbes) . Philippi has recorded it as recent at
Naples (on the authority of Scacchi) and fossil at
Palermo.

My largest specimen is 2^ inches long, and 3| broad.
The young have the same characters as the adult, and
are even more unlike T. papyracea.

The Mya declivis of Pennant, to which it was at one
time referred, appears to have been the half-grown state
of M. truncata. The present species is the Anatina
myalis of Lamarck, and T. Montagui of Leach.

4. T. convex a*, W.Wood.

Mya convexa, W. Wood, Gen. Conch, i. p. 92, pi. 18. f. I. T. convexa,
F. &H. i. p.229, pl.xvi. f. 1,4.

Shell nearly rectangular, extremely gibbous, except towards
the front and posterior side, which are compressed to such an
extent as to give a wedge-like aspect ; it is thinner than T.
pubescens, opaque, and somewhat glossy : sculpture much finer
than that of the last species, and consisting of minute papilla\
which are equally disposed over the whole surface in transverse
and undulating lines ; the marks of growth are slight, but
numerous : colour pale yellowish-brown : epidermis membra-
nous and thin : margins rounded on the anterior side and in

* Convex.

40 ANATINID.E.

front, with a slight indentation towards the posterior side,
which is more or less obliquely truncated, and separated by a
blunt angular ridge in each valve, with an obscwe intermediate
fold, making this side appear bicarinated ; dorsal margins
gently curved : beaks very prominent, obliquely inflected to
the posterior side ; the space below them on each side is deeply
excavated : ligament short and cylindrical, greyish- horncolour,
separating the valves by an elliptical gaj} : cartilage yellowish,
contained in a narrow but solid receptacle, which lies parallel
with the hinge-line, and does not project far within the shell ;
the receptacle is supported underneath by the ordinary rib-like
process : hinge-line obtusely angular : hinge-plate narrow and
slight : ossicle as in the other species : inside yellowish ; edges
blunt : scars nearly marginal. L. 2. B. 2'5.

Habitat : 4-70 f. in suitable parts of the English,
Irish, Scotch, and Shetland coasts ; difficult to procure
on account of its habit of burrowing rather deeply in
muddy sand. Not uncommon in the " alluvial" deposit
at Belfast (Hyndman and Grainger) ; Wexford (Sir
Henry James) ; Coralline Crag (S. Wood) ; " glacial"
formation near Drontheim, 400-500 feet above the
present sea-level (Sars) j Palermo (Philippi). It has
been noticed as a Swedish and Norwegian species by
Loven, Sars, M f Andrew and Barrett, Danielssen, and
Malm, at various depths between 8 and 100 f. ;
M f Andrew dredged it off Gibraltar in 45 f. ; and Martin
obtained it from fishermen on the coast of Provence,
but smaller in size than northern examples.

This handsome shell may easily be recognized by its
almost globular form. The young and fry correspond
in shape with the adult; but they are white and not
so convex, and their dorsal margins are quite straight.
The ligament, as well as the epidermis are wonderfully
preserved in fossil specimens dug out of the clay-bed at
Belfast.

Montagu described it as a large form of T. distorta.

THRACIA. 41

It is the T. declivis of Macgillivrav, T. ventricosa of
Philippic and (apparently) the T. ScheejimaJceri of
Dunker.

B. Posterior side usually larger.
5. T. distor ta*, Montagu.

My a disforta, Mont. Test. Brit. p. 42, t. i. f. 1. T. distorta, F. & H. i.
p. 231, pi. xvii. f. 1, 2, 3, 8, and (animal) pi. H. f. 5.

Body roundish-oval, white : tubes rather short, and some-
what more united towards their bases than in the other British
Thracice ; the branchial or lower tube is often extended more
than half an inch, while the other remains quiescent ; pre-
viously to the former being withdrawn, it is always globularly
inflated at its extremity, which inflation increases until it ex-
tends near the margin of the shell, and the tube then suddenly
collapses ; during the inflation the terminal cirri disappear,
and they only become visible when the tube is at rest : gills
large and brown : palps nearly equal and pectinated : foot
short and linguiform.

Shell varying in shape from round to oval, more or less
distorted and often sinuous, generally convex but sometimes
flattened, more solid in proportion to its size than the other
species, opaque and lustreless : sculpture, minute and crowded
tubercles or granulations of equal size, arranged' in concentric
although irregular rows ; marks of growth distinct : colour
milk-white, with occasionally a yellowish tinge : epidermis
membranous, abraded in front and only to be seen at the
edges, dingy brown : margins rounded on the anterior side
and in front, somewhat truncated or wedge-shaped on the
posterior side, which is in most instances (but not invariably)
larger or more elongated than the other side, and obscurely
angulated ; dorsal margins obtuse-angled : beaks sharp and
entire, slightly inclined to the posterior side ; umbones ra-
ther prominent : ligament short, of various shades of colour
from yellowish to dark brown, separating the valves by an
oval gap : cartilage strong, yellowish -brown or horncolour,
contained in a thick triangular receptacle, which is set ob-
liquely and projects considerably within each valve ; fulcral

* Distorted.

42

ANATINIDyE.

rib indistinct : hinge-line obtusely angular : hinge-plate thick
and strong : ossicle semilunar, slightly attached, and conse-
quently often lost in dead specimens: inside creamcolour, some-
what glossy and nacreous ; edges blunt : scars large and well
defined L. 0-6. B. 0*8.

Yar. truncata. Shell oblong ; front margin straight ; pos-
terior margin abruptly truncated. Anatina truncata, Turton,
Dith. p. 46, t. 4. f. 6.

Habitat : From Guernsey to Unst, in crevices of
rocks and old oyster-shells, between 5 and 35 f ., as well
as occasionally buried in tufts of Corallina officinalis at
low water ; local, but widely diffused. The variety is
from Exmouth, Tenby, and Cork. Fossil in the Coral-
line Crag (S. Wood); Palermo (Philippi). Foreign
range : Finmark to the Cattegat, 3-40 f. (Loven and
others) ; north of France (De Gerville and others) ;
Provence (Martin) ; Algeria (Desliayes and Weinkauff) .

This is the smallest British Thracia ; and its habitat
is different from that of its congeners. It may also be
known by its irregularly oval shape, its less angular
outline, uniform granulation, and comparatively large
cartilage-pit. The young are triangular, and somewhat
resemble a Mont acuta. A full-grown specimen taken
from a narrow chink in a piece of limestone well exem-
plifies the mode in which shells are constructed. Part
of the left valve had been crushed, apparently by acci-
dental pressure ; and in order to repair tlie damage, an
inner layer was formed by exudation from the mantle,
to which the broken fragments were cemented and still
adhere. The distorted growth of this species shows
that it does not excavate the holes in which it lives.
It sometimes appropriates the labours of other animals,
but never unjustly or consciously, like a plagiarist.
The original and short-lived fabricators of the dwellings
subsequently occupied by the Thracia are beyond the

CORBULID.E. 43

power of complaint ; and all that can be said of them is

Sic tos non vobis saxa forate din.

It constitutes the type of Fleurian de Bellevue's genus
Rupicola. Pennant and Donovan described it as Venus
sinuosa, Lamarck as Anatina rupicola, Philippi as Ery-
cina anodon, Anatina ? pusilla, T. oralis, T. fabula, and
T. elongata, Recluz as Rupicola concentrica, and Des-
hayes as T. brevis. Many other species have been made
by Reeve from Mr. Cuming's specimens of this ex-
tremely variable shell. It appears to have been con-
founded bv Kiener with T. corbuloides, Deshaves, on
the supposition that it was a smaller form of that
species.

Another species of Thracia (Amphidesma truncata,
Brown, or T. my op sis, Beck) has been found in glacial
beds, at Greenock by Mr. Stewart Kerr, and at Elie in
Fifeshire by the Rev. Thomas Brown. To this species
appears to have also belonged a shell named " Cochlo-
desma, n. s." by Professor King, which was lately
brought up from the depth of 1000 f. or thereabouts,
100 miles west of Cape Clear, by Capt. Hoskyn in
H.M.S. ' Porcupine ' ; and the fragments of which I
have examined. T. myopsis now lives only in the
Arctic seas.

Family XIX.
CORBUTID.E, (CORBULAME) Fleming.

Body oval or globular : tubes short and united ; excretal tube
furnished with a conspicuous valve : foot long and flexible.

Shell oval, more or less inequivalve and open at the pos-
terior end : heals turned towards the posterior side : cartilage
wholly internal, occupying a horizontal triangular cavity under
the beak in each valve : hinge strong, furnished in some genera

44 CORBULID.E.

with a single erect cardinal tooth in one valve or both, besides
a long lateral tooth on one or each side in either valve ; in
species of Necera there is also a free calcareous ossicle : pallial
scar slight, with a shallow sinus : muscular scars well marked.

These are of small size, and comprised in few genera :
the species are numerous and prolific, characters which
are probably correlative. The British genera are Poro-
mya, Near a, and Corbula. The first is a box studded
with tiny pearls.

" Ne lesse praisworthie faire Necera is."

Her shell resembles the body of a bird, without
feet or wings, but having a stretched-out beak; and,
although this age is not barren of artistic invention,
it might serve as a graceful model for some work of
fictile manufacture. The last has also an apposite
name, and reminds one of a basket with a close-fitting
lid. The hinge in each genus is constructed somewhat
on the plan of the Mactridce ; but it does not possess
an external ligament as well as an internal cartilage.
The Corbulidce live in mud and sand at various depths,
but seldom between tide-marks. Lamarck called them
" Corbulees " Latreille " Corbulsea," and Hinds " Cor-
bulacea."

Genus I. POROMY'A* Forbes. PL II. f. 3.

Body roundish -oval, thin : tubes unequal in size, clothed
with numerous long filaments : foot narrow and slender.

Shell roundish-oval, slightly inequivalve and inequilateral,
thin and pearly, with the outer layer composed of minute
tubercles ; posterior side angulated : epidermis membranous
and thin : teeth, in the right valve a short but strong cardinal,
and in the left a minute triangular cardinal and a ridge-like
lateral on the posterior side.

* Passing into the genus My a ; or having, with the shape of that shell,
a tubular structure.

, TOROMYA. 45

The structure of the shell is very remarkable, although
not differing much from that of Thracia. The external
layer consists of crowded oblong cells having their ends
outward, and the inner layer is nacreous ; the cellular
part is easily rubbed off. The mantle is said to be open
in front, an unusual character in this group. Further
particulars of the animal are desirable.

This genus is the Embla of Loven, and (according to
Chenu) the Eucharis of Recluz.

Poromya granula'ta*, Nyst and Westendorp.

Corhula granv.lata, Nyst & West. Coq. Foss. d' An vers, p. 6, pi. 3. f. 3. P.
granv.lata, F. & H. i. p. 204, pi. ix. f. 4-6, and (animal) pi. W. f. 2.

Body crcamcolour : mantle open in front : tubes encircled at
their bases by a fringe of 18 or 20 tentacular filaments, which
expand like the petals of a flower, and are sometimes folded
back on the posterior side of the shell : foot very transparent.

Shell somewhat quadrangular or rhomboidal (the right
valve larger than the left and slightly overlapping it), mode-
rately convex, fragile ; externally it is opaque and of a dark
hue, but when the superficial or granular coating is removed,
it is semitransparent and glossy : sculpture, very minute and
close-set tubercles of nearly equal size, arranged in longitu-
dinal rows, and occasional but slight marks of growth : colour
dusky outside, and whitish under the surface-layer : epidermis
dark brown, visible only at the edges, and especially at the
back (where it forms a kind of elongated ligament on both
sides of the beak) : margins] rounded on the anterior side,
slightly curved in front, indented near the posterior side, which
is obliquely truncated and has a distinct ridge extending from
the beak to the posterior angle, with a broad fold on either
side of it ; posterior dorsal margin longer and straighter than
the other : beaks blunt and calyciform ; umbones prominent :
cartilage yellowish -brown, set rather obliquely in an obtusely
angular receptacle, which does not project far within : hinge-
line gradually curved : hinge-plate thickened on both sides of
the beak : teeth, in the right valve an erect, blunt and tuber-

* Granulated.

46 corbulidjE.

cular cardinal ; in the left valve a small, sunken and triangular
cardinal, besides a long but slight laminar lateral on the pos-
terior side : inside glossy and nacreous, closely but obscurely
lineated lengthwise ; edges sharp : muscular scars triangular,
lying near the dorsal margins. L. 0-325. B. 0-375.

Habitat : In mud among boulders, 40-45 f., close
to Croulin Island, and in another part of the Sound of
Skye ; rare. Mr. Dawson found a worn and imperfect
valve in shell-sand from Haroldswick Bay in the north
of Shetland. Coralline Crag (S. Wood) ; newer tertiary
beds near Antwerp (Nyst and Westendorp). Koren
got it at Bergen ; M f Andrew and Sars dredged it off the
coasts of Finmark, the former in 45-90 f. ; Deshayes
obtained it from Sicily and Bona, and Tiberi at Naples ;
Forbes in the iEgean between 40 and 150 f . ; and
M f Andrew at Madeira in 20 f.

Clark conjectured that this might be the young of
Thracia convexa, and he said that the present species
has an ossicle in the hinge ; but he did not see with my
eyes. I have compared specimens of P. granulata and
T. convexa of all sizes, from the fifteenth of an inch in
length. Each exhibits a marked difference of outline :
one is square, and the other triangular. I have also
examined perfect examples of the Poromya from Scan-
dinavia, Skye, and Naples ; and in none of them could
I detect an ossicle or any space for it. He also stated
that the siphons of these two mollusca are equally short,
and ornamented with cirri or filaments ; but neither of
these characters was noticed by him in his elaborate
account of the only species of Thracia described in the
' History of the British Marine Testaceous Mollusca/
and he admitted that he had not seen the animal of T.
convexa or of P. granulata.

Forbes described the recent shell as P. anatinoides,

NE.ERA. 47

Loven as Embla Korenii, Deshayes as Corbula vitrea,
and Tiberi as Cuminyia parthenopcea.

Genus II. NE-ER'A*, (NEARA) Gray. PL II. f. 4.

Body globular, thin : tubes unequal in size, clothed with a
few long filaments : foot lanceolate.

Shell fig-shaped, inequilateral, thin ; posterior end twisted
and extended into a beak-like process : epidermis membranous :
teeth, sometimes a small cardinal in each valve, of a crest-like
laminar lateral on the posterior side of one valve or both ;
certain species have also a free calcareous ossicle.

The late Capt. Brown first suggested the generic
separation of the present group of shells, which are
distinguished no less by the singularity than by the
elegance of their shape. His services in the cause of
British conchology would have been greater if his
attention had not been distracted bv so many other
branches of zoology. Good results, however, were pro-
duced by his publications, especially in promoting the
faculty of observation in young persons. Clark repu-
diates the genus, and merges it in Anatina, on the
ground that each has an ossicle. This leads to the
consideration of the difficult question, what is a genus ?
Nor can I agree with him that we have but one species
of Neara. Perhaps in a few centuries hence, or sooner,
his opinion on the last point may be found correct ; or
possibly the very notion of species may be classed among
the vulgar errors of a half- enlightened age. What our
Poet-laureate savs is true, that

" Science moves, but slowly slowly.
Creeping on from point to point:"

or as Seneca puts it, " Multa hoc primum cognovimus

* A Sea-Nymph mentioned by Spenser.

48 CORBULID.E.

sseculo, multa venientis sevi populus nobis ignota sciet ; f
but at present my opinion coincides with that of other
naturalists, both as to the existence of species, and of
those of Necera in particular.

This genus is the Cuspidaria of Nardo. It contains
many exotic species ; the late Mr. Hinds described and
enumerated seventeen in the ' Proceedings of the Zoo-
logical Society' for 1843, and Mr. A. Adams several more
in the f Annals and Magazine of Natural History ' for
March 1864. The name Near a was originally used for
a genus of Diptera ; but no one is likely to be misled
by the subsequent application of it to the Mollusca,
unless perchance in consulting an index to any work on
general zoology. Otherwise the name given by Nardo
is more characteristic.

1. NeyEra abbrevia'ta*, Forbes.

Ni abbreviata, Forbes in Zool. Soc. Proc. 1843, p. 75: F. & H. i. p. 201,
pi. vii. f. 7.

Shell triangularly oval, obliquely twisted to the posterior
side, nearly equivalve, extremely gibbous, fragile, sernitrans-
parent, slightly glossy and iridescent : sculpture, about a dozen
concentric plaits or folds, besides numerous fine but irregular
intermediate striae ; the surface is also marked by a few obscure
longitudinal lines, and the posterior side by a sharp rib which
runs outwards from behind the beak in a curved or flexuous
direction : colour greyish- white : epidermis yellowish-brown,
visible only at the edges and back : margins rounded on the
anterior side and in front, indented or nexuous on the posterior
side, which is short, wedge-like, and considerably compressed ;
dorsal margins nearly equal in length, and straight : beaks
blunt, much inflected, somewhat inclined to the anterior side ;
umbones prominent ; the dorsal area is deeply excavated :
cartilage small, yellowish-brown, occupying an elliptical cavity
in a parallel line with the hinge : hinge-line obtusely angular :
hinge-plate narrow : teeth, a minute thorn-like cardinal in each

* Shortened.

NE.ERA. 49

valve, and a slight lateral on the posterior side of the right
valve : inside glossy and nacreous ; posterior side separated by
a sharp rib : scars indistinct. L. 0*8. B. 0-4.

Habitat : Loch Fyne (M' Andrew and Barlee) ; Skye
and Shetland (Barlee) ; in 40-75 f., on a muddy
ground. Fossil in the Belgian tertiaries (Nyst). Its
known distribution elsewhere in a recent state is as
follows : — Bohuslan (Loven) ; Christiania, 40-100 f.
(Asbjornsen) ; Bergen, 40-50 f. (Danielssen) ; Fin-
mark (Sars and Lilljeborg) ; dead valves in the iEgean,
75-105 f. (Forbes) .

It is the N. vitrea of Loven.

2. N. costella'ta*, Deshayes.

Corbala costellata, Desh. Exp. Scient. Mor. (Geologie) p. 86, t. vii. f. 1-3.
N. costellata, F. & H. i. p. 199, pi. vii. f. 8, 9, and (animal) pi. G. f. 8, 9.

Body gelatinous, clear white : mantle so transparent as to
allow the pink gills and dark brown liver to be seen through
it : tubes cylindrical, sometimes yellow with reddish or orange
markings, and tinged with brown at their extremities; ex-
cretal tube much the smaller of the two ; tentacular cirri white
and plain, extending beyond the tubes ; orifices fringed : foot
narrow.

Shell more slender than N. abbreviate, more ineqnivalve,
much less ventricose and even somewhat compressed, equally
fragile, semitransparent, glossy and iridescent : sculpture.
20-30 longitudinally radiating ribs, which are slighter and
more like striae on the anterior side and in front, but stronger
and more distant towards the posterior side, especially the last
two or three ; these ribs vary in size and fineness ; the pro-
longed part on the posterior side is also marked with two or
three slight ribs, which are parallel with the dorsal line and
extend to the rostral point : colour and epidermis as in the
species last described : margins also similar, except behind,
where the anterior dorsal margin is raised and appears high-
shouldered, and the posterior dorsal margin is inflected and

* Fine-ribbed.
VOL. III. D

50 corbulid^e.

curved ; rostral prolongation considerable, much more attenu-
ated than in the other species : beaks small and mammillary ;
unibones by no means prominent ; dorsal area narrowly exca-
vated on the posterior side : cartilage orangecolour, contained
in a triangular receptacle which shelves outwards : hinge-line
straight : hinge-plate narrow and slight : teeth, an extremely
minute tubercular cardinal in the left valve, and a strong
erect and triangular lateral in the right valve on the posterior
side : inside glossy, with a rib on the posterior side : muscular
scars well marked ; anterior irregularly oblong, posterior tri-
angular. L. 0-25. B. 0-415.

Var. lactea. Shell milk-white, more glossy, transparent,
and delicate, having only two ribs on the posterior angle,
besides those on the rostral process.

Habitat : Loch Fyne, 40-70 f., with the last species
(M f Andrew and Barlee) ; Cumbrae, Firth of Clyde
(Robertson) ; Skye and Shetland (Barlee and J. G. J.) .
The variety was dredged by me on a sandy bottom, in
78 f., from 40 to 50 miles east of the Whalsey Skerries,
Shetland. Upper tertiaries of Greece (Deshayes) ;
Antwerp (Nyst) ; Guise-Lainotte, France (De Koninck) ;
Calabria (Philippi). It inhabits the coasts of Scandi-
navia at depths ranging between 10 and 100 f. (Loven
and others) ; Carthagena, in 30 f., and Gibraltar, in 45 f.
(M ( Andrew) ; Provence, in 60 f. (Martin) ; Gulf of
Genoa, in 25 f. (J. G. J.) ; Adriatic (Chiereghini) ;
Naples (v. Martens) ; iEgean, in 20-185 f. (Forbes) ;
Malta, in 40 f., Gulf of Tunis, in 35 f., Madeira, in
18-24 f., and Teneriffe, in 20-35 f. (M'Andrew).
Specimens dredged by the late Professor Barrett in
deep water at Jamaica are scarcely distinguishable from
those of the North Atlantic.

This exquisite shell cannot well be mistaken for
N. abhreviata ; their shape, sculpture, and dentition are
very different.

Nvst seems to have been the earliest describer of it,

NE.ERA. 51

as Corbula Waelii ; and the figures which he also gave
are very exact. This was in 1843. The great French
work on the expedition to the Morea was published
eight years previously. Bory St. Vincent contributed
the geological portion of this work, which contains a
good representation of the shell ; the only other notice
of it appears in the index to the plates, where it is
entered as " C. costellata, Deshayes/' It is the N. sul-
cata of Loven, C. rostrato-costellata of Acton, and Tel-
Una naticuta of Chiereghini. The figures in Philippi's
work on the Sicilian Testacea are not satisfactory ; they
were probably made up or " restored/' for he says that
all his specimens were " paullulum lsesas."

3. N. rostra ta*, Spengler.

My a rostrata, Spengl. in Skrivt, Selsk. iii. p. 42, t. 2. f. 16.

Shell resembling a fig with a broad stalk, nearly equivalve
except in the young, convex, more solid than the preceding
species, opaque and almost lustreless : sculpture, numerous
but slight concentric raised striae or wrinkles, becoming more
crowded and flexuous towards the posterior side; the upper
angle on that side (which forms a long and diagonal crest or
ridge, extending from behind the beak in each valve to the
rostral point, and defined by an oblique rib) is crossed by
close- set and somewhat curved striae at a right angle to the
transverse markings on the body of the shell : colour whitish :
epidermis more persistent than in the other two species, pale
yellowish- white : margins rounded on the anterior side and
immediately in front, bending upwards and nearly in a straight
course to the deep sinus or indentation caused by the exten-
sion of the posterior side ; this part is remarkably twisted and
elongated, being about two-fifths of the entire breadth of the
shell ; posterior dorsal margin curved inwards ; anterior dorsal
margin high-shouldered : beetles inflected ; umbones rather
prominent ; dorsal excavation deep, wide on the anterior and
narrow on the posterior side : cartilage small, golden-yellow,

* Beaked.

d2

52 . CORBULIDiE.

contained in an oval pit, which projects obliquely inwards ;
the cartilage is held together by a calcareous band or ossicle,
placed as in Lyonsia, which is easily split and broken in two
when the valves are separated ; it then curls up, so that each
half resembles the shelly appendage peculiar to Thracia :
hinge-line straight : hinge-plate moderately broad : teeth, a
lateral in each valve, which is triangular, erect, and rather
long in the right valve, ridge-like and slight in the left : inside
glossy and nacreous, obscurely striated lengthwise : scars in-
distinct. L. 0-45. B. 0-8.

Habitat : East coast of Shetland, 40 miles off the
land, in 76 f., soft and muddy sand ; a right valve only,
with living specimens of the common kind, N. cuspidata.
The foreign localities are, Bergen, among Oculina pro-
lifer a (Spengler) ; other parts of Norway, at various
depths from 10 to 130 f. (Loven, Asbjornsen, Danielssen,
and Sars) ; Sweden, 20-60 f. (Loven and Malm) ;
Gulf of Lyons, 80-100 f. (Martin) ; Toulon (Thor-
rent) ; Genoa (J. G. J.) ; Naples, 30-40 f. (Tiberi) ;
Sicily (Philippi) ; and iEgean, 110-150 f. (Forbes).
The N. Chinensis of Gray, from Mr. Hinds's explorations
in the East Pacific, is closely allied to this species, if not
identical with it.

This is a larger and stronger shell than N. costellata,
much more elongated in proportion, and has a different
kind of sculpture.

It is apparently the Anatina longirostris of Lamarck,
and Corbula cuspidata of Brown, as it is certainly the
N. attenuata of Forbes, and N. renovata of Tiberi. I
have examined the types of these last two, as well as of
Spengler's species. Of the two figures given by Philippi
(vol. i. tab. i. f. 19) that on the left hand represents the
present species, and the other (which is drawn partly
from imagination) JV. cuspidata.

4. N. cuspida'ta*, Olivi.

Tellina cuspidata, Olivi, Zool. Adr. p. 101, tab. iv. f. 3. N. cuspkkita.
F. & H. i. p. 195, pi. vii. f. 4-0, and (animal) pi. Gr. f. 4-7.

Body greyish, or dirty white : mantle rather thin : tubes
nearly sessile, sometimes mottled with pink ; orifice of lower-
one fringed with 5 or 6 short cirri ; the base of each tube is
encircled by 6 rather long and slender filaments, which have
cup-shaped extremities, like the polypidoms of many zoophytes ;
these filaments occasionally are knotted or studded at intervals
with bulbs of an azure hue ; the orifice of the upper or excreta!
tube is plain, but provided with the usual hyaline valve : foot
long, flexible, and white.

Shell obliquely triangular (left valve sensibly larger than
the right), extremely gibbous and tumid, moderately solid,
opaque, and almost lustreless : sculpture, numerous slight and
irregular concentric striae or wrinkles, becoming closer and
JlexuQUs towards the posterior side ; the upper angle on that
side is crest-like and striated as in N. rostrata, but it is not
so distinctly defined, nor elongated to anything like the same
extent : colour whitish under the epidermis, which is light
chestnut or reddish-brown, thick (especially at the dorsal edges,
where it has somewhat the appearance of a ligament), some-
times coated with sand or mud : margins rounded on the an-
terior side as well as in front, with an abrupt and deep sinus
on the posterior side, which is somewhat twisted and compa-
ratively short, being about one-half of the entire breadth of
the shell ; posterior dorsal margin incurved ; anterior dorsal
margin forming a rounded slope, but not projecting as in the
last species : beaks inflected, and interlocking, or placed one
on each side instead of opposite ; umbones extremely promi-
nent ; dorsal excavation deep, heart-shaped on the anterior
side, and trench-like on the posterior : cartilage and ossicle as
in N. rostrata, but the former is horncolour, and the pit does
not project so far inwards : hinge-line obtusely angular : hinge-
plate thick : teeth, a strong recurved and rather short trian-
gular lateral in the right valve, and only an obscure and blunt
laminar lateral in the other valve : inside glossy, porcellanous,
and nacreous, indistinctly striated lengthwise ; it is furnished
on the posterior side in each valve with a thick rib, extending
from below the beak half-way across to the indentation that

* Pointed.

54 CORBULID.E.

defines the snout-like process : pallial scar well marked, with
a semicircular sinus : muscular scars rather deep ; anterior
irregular, posterior triangularly oval. L. 0-55. B. 0-8*

Var. 1. curia. Rostral or snout-like process shorter.

Var. 2. cinerea. Shell ashcolour, and thinner.

Habitat: Land's End (M' Andrew) ; Northumberland
and Durham (Brown, Thomas, Alder, and Mennell) ;
Aberdeen (MacgilliA^ray) ; Firth of Forth (Gerard and
Thomas) ; throughout the west of Scotland (Smith and
others) ; Shetland (M' Andrew and others) ; off Cape
Clear (M f Andrew) ; Arran Isle, Galway (Barlee) ; in
muddy sand, at depths varying from 12 to 82 f. Var.
1 and 2. Hebrides (Barlee). Searles Wood has recorded
this species as fossil in the Coralline Crag, Risso from
Nice, and Philippi from Sicily ; upper miocene bed near
Antibes (Mace). Its foreign distribution in a recent
state comprises Spitzbergen and South Greenland
(Torell) ; Scandinavia, 22-180 f. (Loven and others) ;
Carthagena and Gibraltar, 45 f. (M f Andrew) ; Provence,
in a gurnard's stomach (Martin) ; Italian coasts of the
Mediterranean (Maravigna and others) ; Adriatic (Olivi
and Chiereghini) j Malta, 40 f. (M f Andrew) ; iEgean,
12-185 f. (Forbes) ; Algeria (Deshayes and others) ;
Madeira, in 18-24 f., and Teneriffe, in 20-35 f.
(M f Andrew). Mr. Hinds, after giving some European
localities, remarks, " Nor can I perceive any difference
in the valve of a shell obtained from 84 f. in the China
Sea ; the temperature below being 66°, and at the sur-
face 83°/'

It is much more globular and obliquely twisted than
N. rostrata, and it is more finely striated ; the snout in
all specimens is considerably shorter ; the front or ven-
tral margin is more curved; and the posterior dorsal
side is abruptly truncated, and not so rounded and pro-

CORBULA. 55

minent as in that species. The young of Loch Fyne
specimens are proportionally more slender than the
adult, and more elongated in the line of the major axis ;
but they essentially differ from N. rostrata of the same
age or size. A valve which I dredged in deep water off
the east coast of Shetland is nearly an inch broad, and
coarsely wrinkled : it agrees with specimens which I
examined in the Museum at Christiania, described bv
Sars as N. arctica, as well as with some dredged by
Torell in the Arctic Sea.

Brown called the present species Anatina brevirostris
and Thracia brevirostris, and Nardo Cuspidaria typica.

Genus III. COB/BULA*, Bruguiere. PL II. f. 5.

Body oval, rather thick : tubes seldom protruded ; orifices
fringed : gills 2 on each side, unequal-sized : palps corre-
sponding with the gills in number and position, but equal in
size : foot tongue -shaped and thick.

Shell oval, nearly equilateral, rather solid ; posterior side
wedge-shaped : teeth, a short and strong cardinal in each valve,
and a ridge-like lateral on both sides of the right valve.

The structure of the shell is like that of the Anati-
nidce : according to Carpenter " the outer layer is com-
posed of large fusiform cells, whilst the inner is nearly
homogeneous." Searles Wood informs us that fossil
species have been found as early as in the lower Oolite.

Miihlfeldt called this genus Aloides ; and modern
systematists have invented for it other equally ill-
compounded names, such as Spenser, in his ' Teares of
the Muses/" designates

"Heapes of huge words uphoorded hideously.
With horrid sound though having little sence."

* A little basket.

56

CORBULID.^.

CoRBULA GIBBA"*, Olivi.

Tellina gibba, Olivi, Zool. Adr. p. 101. C. nucleus, F. & H. i. p. 180, pi. ix.
f. 7-12, and (animal) pi. G. f. 3.

Body whitish, with often a tinge of yellow : mantle thick ;
its edges minutely ciliated : tubes contiguous, very short, and
scarcely protruded beyond the valves, edged with narrow lines
of pink or orange a little below the extremities ; orifices fringed
with conical and rather slender cirri or tentacles (from 8 to 12
round each), having truncated points ; these cirri are trans-
parent, and spotted with a few flake- white marks, and each is
encircled at its base by a line of red dots ; hyaline apparatus
of the upper tube bell-shaped, retractile, and in frequent
action : gills very unequal, hanging obliquely, the upper one
narrow, and the lower one larger and more triangular ; they
are brown, smooth outside and finely striated within : palps
long, narrow, pointed, pendulous, and brown, pectinated
strongly on both surfaces : foot large and thick, very fleshy,
bent near its junction with the rest of the body, sometimes
forming an elongated cone and byssiferous : liver dark green.

Shell triangularly oval ; right valve much larger and more
gibbous than the left, which it overlaps to a considerable ex-
tent ; left valve compressed towards the front and sides ; the
substance is thick and opaque, and the surface of the right or
deeper valve is more glossy than that of the other, and occa-
sionally iridescent : sculpture, numerous concentric stria?, which
in the smaller valve are slight and irregular, and are often
crossed by a few raised lines radiating from the beaks, but in
the larger valve these stria? usually become cord-like and close-
set ribs : colour white, with more or less of a yellowish or
reddish-brown tinge, sometimes varied by longitudinal rays or
streaks of the latter hue on the larger valve : epidermis brown,
thick, and somewhat fibrous, mostly abraded and wanting on
the larger valve : margins rounded on the anterior side and in
front, truncated on the posterior side (which is depressed and
diagonally separated in the smaller valve, and twisted in the
other valve), with a slight groove or fold proceeding from below
the beak ; dorsal margins straight : beaks calyciform, obliquely
incurved to the anterior side ; umbones prominent and conti-
guous ; dorsal excavation generally deep, but not distinctly
defined : cartilage small, narrow, and triangular, composed of
several leaflets, which represent the successive accretions of

* Gibbous.

CORBULA. 57

growth ; it is contained in a cavity or depression of the car-
dinal tooth in the left valve : hinge-line obtusely angular :
hinge-plate rather broad and strong : teeth, in the right valve a
thick, pyramidal, and recurved cardinal, besides a long ridge-
like lateral on each side ; in the left valve a thick cardinal,
which resembles in shape the bowl of a spoon, and may be
considered the cartilage-pit, although it is not horizontal and
it slopes upwards from the beak ; close to it on the anterior
side of the same valve is a cavity for the reception of the oppo-
site tooth : inside porcellanous and glossy, microscopically and
closely wrinkled, more or less stained with coffeecolour ; edges
somewhat bevelled : pallial scar slight, with an extremely
shallow sinus : muscular scars distinct ; anterior oval, posterior
nearlv circular. L. 0-5. B. 0-6.

Var. rosea. Shell rather more oval and glossy, with a
purplish streak on either side of the beak in each valve, and
the rays on the larger valve of a more vivid hue. C rosea,
Brown, 111. Conch, p. 105, pi. xlii. f . 6 ; F. & H. i. p. 185,
pi. ix. f. 13, 14.

Habitat : Gregarious in sand, mud, and gravel on
every part of our coasts. I once found live specimens
burrowing in the sand at Oxwich Bay, Glamorganshire,
on the recess of an unusually high spring tide ; and it
occurs as deep as 72 f. in Shetland. It usually frequents
the laminarian zone. The variety is equally diffused in
the British seas, and ranges from Norway to the Medi-
terranean ; Weinkauff has taken it at Algiers in brackish
water. C. gibba is not uncommon in post-pliocene and
pliocene deposits, e. y. at Belfast (Grainger) ; raised
beach at Moel Tryfaen (Darbishire) ; Scotch and Irish
glacial beds (Smith) ; Norwich Crag at Bramerton
(Woodward) ; Red and Coralline Crag (Wood) ; " gla-
cial }} formation near Christiania (Sars) ; Nice (Risso) ;
Belgian tertiaries (Nyst) ; Sicily (Philippi) ; and I no-
ticed it in M. Mace's collection of upper miocene fossils
from Antibes. In a recent state it is universally distri-
buted throughout the North Atlantic, from the Loftbden

D O

58 CORBULID^.

Isles to the iEgean and Canaries, at depths of from 4 to
80 f.

Our northern shores seem to produce the largest
specimens, those from the Channel Isles being more
brightly coloured. The fry have a squarish outline,
and are highly polished. This species varies both in
shape and sculpture, from oval to round, and from
ribbed to smooth. The shell is subject to the attacks
of predatory mollusks, which do not always succeed in
perforating it : in such cases the white outside layer
only is removed, exposing the succeeding layers, which
are of a firmer texture and coffeecoloured. Aucapitaine
states that he found specimens of a smaller size and
paler colour than usual, living abundantly in brackish
water at Rochelle, often floating on grasses half covered
with water, and sometimes buried in mud to the depth
of their siphons.

It is the Cardmm striatum, &c, of Walker, My a in-
(squivalvis of Montagu, Corbula nucleus of Lamarck, and
C. olympica of Costa ; several other specific names have
been given to it by palaeontologists.

Among the shells collected by Mr. J. D. Humphreys
at Cork were a few specimens of C. mediterranea, Costa,
mixed with C. gibba. Philippi referred this species to
the Tellina parthenopma of an unpublished work by
Delle Chiaje; and it appears to be also the C. physoides
of Deshayes's ' Mollusques d'Algerie/ The Irish speci-
mens may have been imported (as well as Petricola
lithophaga) in ballast, and I therefore merely indicate
the possibility of its being indigenous ; but this species
is interesting in connexion with another shell, which I
have now to mention. In the ' Malacologia Monensis '
of Forbes will be found a short description, but charac-
teristic figure, of a species named by him C. ovata. It

CORBULA. 59

was established on a single specimen " taken from the
root of a fucus cast ashore at Ballaugh. ' Dr. Morch
gave me the same species, which he had procured from
Greenland. It is undistingnishable from C. mediter-
ranea, except in its much larger size and the absence of
coloured streaks ; in shape, sculpture, and peculiar den-
tition it corresponds exactly with the Irish specimens,
and with some from the Gulf of Lyons, for which I am
indebted to the kindness of M. Martin. I cannot help
conjecturing that the Manx shell might have been
brought to this country with others from the Arctic
seas, and have afterwards become accidentally mixed in
Forbes' s collection; especially when I remember that
he sent me about the time of his publishing the
' Malacologia/ and when he was almost a tyro in British
conchology, another shell for my opinion. This was
Venus fluctuosa, a native of the North- American seas.
The memorandum accompanying the last-mentioned
shell stated that it had been received by Forbes, as
picked up on the shore at Leith, but not by himself.
The difference of size between Greenland and Mediter-
ranean specimens of the same species further exemplifies
my remarks in the first volume on this subject.

The late Dr. Lukis sent me specimens of C. labiata,
a handsome South-American species, with which the
tide-mark in a small bay in Guernsey had been strewn
in November 1859, immediately after the wreck of a
ship in ballast from Buenos Ay res. Along with this
Corbula were found a small Melania and other tropical
shells. This shows the importance of carefully studying
the geographical distribution of the Mollusca, in order
to avoid errors likely to result from accidents of the
above kind. Otherwise all these shells might be de-
scribed or enumerated as British.

(30 myidjE.

Family XX. MY'ID^E, (MYAD.E) Fleming.

Body oval : mantle rather thin, except at the edges : tubes
united, and wholly enclosed in a tough, leathery, brown sheath ;
orifices fringed : gills of moderate length, unequal on each side,
and striated : 'palps triangular, striated like the gills : foot
tongue-shaped, furnished with a byssal groove.

Shell oval or oblong, somewhat inequivalve, usually gaping
at both ends, but more widely on the posterior side : epidermis
membranous : beaks more or less contiguous, not prominent,
turned towards the anterior side : cartilage internal, contained
between a perpendicular spoon-shaped and fixed receptacle,
lying under the beak in the right valve, and a cavity of the
cardinal tooth or process in the left valve : hinge strong, fur-
nished with a small cardinal in the right valve, and with an
erect triangular tooth in the left valve, which latter tooth is
strengthened by an inside flange on the posterior side ; this
tooth is not inserted into the hinge of the right valve, but is
merely attached by the cartilage to the sunken receptacle
above mentioned : pallial scar broad and deeply sinuated :
muscular scars large and strongly impressed ; anterior elon-
gated, posterior triangular.

The typical genus My a is the only one that I con-
sider British. There seems to be no valid reason for
separating Sphenia (Turton) from it, either in respect
of the animal or of the shell. The so-called Panopea
Norvagica has a very different kind of hinge, besides
an external ligament : it belongs to Saxicava. So far
as is at present known, the My a or " gaper " family is
restricted to the northern hemisphere. They inhabit
sand and mud, usually in the lowest part of the littoral
zone.

Genus MYA* Linne. PL III. f. 1.

The characters have been already given in the description
of the family.

* So named from a supposition that it was the fiv$ of ancient writers.

MYA. 61

It is impossible to say what were the fives of Aristotle,
except that they were not our shells ; nor is it probable
that the latter could have come within the scope of his
observation, inasmuch as thev are not natives of the
Archipelago. The fives w r ere included by him with the
xreves (or Pectens) among the bivalves, but they were
said to produce spawn-capsules, like the 7rop<f)vpa or
Murex trunculus. iEschylus, Atlienseus and other Greek
writers also mention fives, but only in such a way as to
show that thev were an eatable kind of shell-fish. The
Myes of Pliny, that indefatigable naturalist with so
little originality, were described by him as " run ac
parvi." They may have been Mytilus edulis. The hinge
in the present genus resembles that of Thracia in struc-
ture, but not in position. In the last-named genus the
process in each valve is horizontal, and projects inwards •
but in My a it is perpendicular or erect in one valve,
and depressed in the other. In each case the office is the
same, namely to contain the cartilage. Messrs. Alder
and Hancock have carefully investigated the nature of
the "branchial currents'''' in My a as well as Pkolas,
produced by the action of cilia, and admitted and dis-
charged by different apertures ; and the following extract
from their excellent paper on the subject, which ap-
peared in the 'Annals and Magazine of Natural History'
for November 1851, will explain to those who have not
studied the economy of the Bivalve Mollusca how this
operation is performed, ff We lately had an opportunity
of observing Mya arenaria in its native haunts, and
watched the play of its siphonal currents under very
favourable circumstances. This species, at the mouth
of the Tyne, buries itself to a depth of 6 or 8 inches in
a stiffish clay, mixed with shingle ; and in shallow r pools
left by the tide, the siphonal tubes may be seen just

62 MYlDiE.

level with the surface of the muddy bottom in full action.
The mud lies closely packed against the walls of the
tubes, so that nothing is to be seen but the internal
surface of the expanded lips of the siphonal orifices
fringed with numerous tentacles. When it happens
that the surface of the water is only a little above these
orifices, a strong current can be distinctly seen to boil
up from the anal siphon, and another, with a constant,
steady flow, to set into the branchial one. These cur-
rents were quite visible to the naked eye without the
aid of a glass, so long as the mollusk remained undis-
turbed. We watched one individual for nearly a quar-
ter of an hour, and no interruption of them took place,
and it was not until the siphon was touched, that the
tubes were withdrawn and the current ceased to play.
.But the siphon soon made its appearance again at the
surface, and the orifices once more expanding, the cur-
rents commenced to play as strongly as ever

On removing these animals from their concealed abodes,
and placing them in a vessel of fresh sea-water, the two
siphonal currents were generally found in action when
the individuals were undisturbed. And further, on
placing the shell with its back downwards and the pedal
gape raised above the surface of the water, these currents
still continued to play ; the excurrent and incurrent
being as distinctly observed as before." The authors
of this paper also ascertained that the currents commu-
nicate through minute openings in the laminae of the
gill-plates, which are sieve-like, filtering and collecting
all the nutritious particles imbibed through the inhalant
tube, in order that they may be carried to the mouth
by the labial palps. Mr. Clark opposed the above view
of the case, and endeavoured to prove that the water
was mainly, if not altogether, introduced through the

MYA. 63

pedal opening ; but although this mode of introduction
may take place to a certain extent when the My a or
Pholas is removed from its hole, and placed in a vessel
of water (after having ejected the greater part of its
fluid contents, so as to create a vacuum) , it is difficult
to conceive how the requisite supply of food and
water can be thus procured while the Mya is imbedded
several inches in impervious clay or the Pholas is en-
closed in its stony cell, or what in either of the above
cases would be the use of the larger tube. I have
repeatedly witnessed in many kinds of Bivalve Mollusca
a current charged with animalcula or molecules being
absorbed by this tube in a continuous stream, and a
limpid current discharged at the same time by the
smaller tube, occasionally together with pellets of faecal
matter or other rejectamenta. The structure of the
shell has been investigated by Dr. Carpenter, and found
to consist of variously formed cells : in the tooth or
hinge-process is seen a group of large cells, the calcareous
contents of which are arranged on a very regularly radi-
ating plan, like that of the mineral called Arragonite
or Wavellite. Neither in the shell nor in the tooth is
there animal matter enough to give anything more than
a delicate membranous residuum, in which no vestige
of cell-walls can be detected.

This genus is modern in a geological sense, and does
not occur in any formation older than the upper terti-
aries. Only three species live in the European seas,
the larger two of which are edible.

64 MYIDJE.

1. Mya arena'ria"*, Linne.

M. armaria, Linn. S. N. p. 1112 ; F. &H. i. p. 168, pi. x. f. 4-6.

Body fleshy, yellowish-white ; tubular sheath covered by
an extension of the epidermis of the shell ; orifices of the tubes
tinged with red, and fringed with tentacles of different sizes.

Shell oblong (the right valve a trifle larger than the left,
the inequality being more observable in young specimens),
equilateral, gaping considerably at both ends, compressed,
rather solid, opaque, usually lustreless : sculpture, coarse and
irregular concentric striae, diversified by stronger marks of
growth : colour ashy-grey, with often a ferruginous tinge, or
variegated by radiating lines of a brownish hue, which are
caused by slight longitudinal folds of the epidermis : the latter
is thin, yellowish brown, fibrous at the sides and in front, and
imparting an oblique striation to the surface of the shell :
margins rounded on the anterior side, slightly curved in front,
and wedge-like on the posterior side ; dorsal margins sloping
more on the posterior than anterior side ; posterior side ob-
scurely keeled : beaks small, inflected, placed close together,
that of the left valve being worn away or broken by continual
pressure : cartilage triangular, strong, horncolour : hinge-line
almost straight : hinge-plate broad and thick : teeth, in the
right valve a slight and oblique cardinal on the anterior side
of the cartilage-pit ; the left valve has the complicated process
described as one of the characters of the family, which in this
species is very large, and irregularly shaped, convex within
and concave without; the spur-like flange on the posterior
side is placed obliquely, and there is a deep groove next to the
hinge-plate for the reception of a blunt tooth-like fold on the
same side in the opposite valve : inside chalky-white : scars
distinct and deep. L. 2-5. B. 4.

Var. lata. Shell dwarfed, more oval and solid. M. lata,
J. Sowerby, Min. Conch, t. 81.

Monstr. Furnished inside with foliaceous plates, showing
a laminated structure.

Habitat : Common on many parts of the coast, at
low-water mark ; chiefly in estuaries, where there is an
admixture of fresh water with the sea. The variety is

* Inhabiting sand.

MYA. 65

from the Firth of Forth and Oban, and the abnormal
form from Exmouth. Fossil in all our newer tertiaries
up to the Red Crag; inclusive ; Nieuwerdiep, Friesland,
in excavating the Royal naval dock (J. G. J.) ; newer
beds of the " glacial formation " at Christiania, 50-
.200 feet above the level of the sea (Sars) ; Belgium
(Nyst) . In a living state M. arenaria is universally
spread over the shores of the western hemisphere as far
south as New York (de Kay), and the eastern hemi-
sphere as far south as Rochelle (D'Orbigny, pere), and
between the 30th and 40th degrees of latitude in China
(Debeaux) . Dr. Walker records it from South Green-
land at depths of from 10 to 120 f. ; and on the coast
of Norway it is enumerated by Danielssen as taken in
2-15 f., and bv M f Andrew and Barrett in 20-40 f.
It is, however, in the main a sublittoral species.

M . arenaria received its name from Baster, and its
habits are well described in his ' Opuscula subseciva/
He says that the foot, with which it penetrates the sand
or mud, is wonderfully flexible, and assumes various
shapes — now a trepan or pointed graving-tool, then a
sharp wedge, a bent hook, or else a spade or dibble —
each shape being adapted to some mode or other of
boring, displacing, or removing the material in which
this mollusk makes its abode. It is eaten and relished
by man and fish in Europe, Asia, and America. At
Southampton the fishermen used to call it " old maid"
according to Montagu ; and at Belfast it has the equally
strange name of f f Cockle-briilion." It forms one of the
numerous articles of Chinese diet, being brought to mar-
ket after having been boiled for a long time, and cooked
with a seasoning of which onion is the base ; the people
call it " Tse ga." The occurrence of this circumpolar
shell-fish so near the tropic of Cancer probably indicates

66 MY1D.E.

the most southern limit in space of the glacial epoch.
In the United States it goes by the general name of
" clam " ; and Gould informs us that it is more import-
ant, in an economical point of view, than the oyster.
About 5000 bushels are annually brought to Boston
market alone as food for man; and much more than
ten times that quantity is salted and used as bait for
fish. Its capability of living in brackish and even fresh
water is well known. Lindstrom has given the following
list of Mollusca associated with it in the Baltic : Neri-
tina fluviatilis, Bythinia tentaculata, Physa fontinalis,
Limncea st agnails, L. auricularia, L. peregra, Tergipes
lacinulatus, Limapontia nigra, Mytilus edulis, Cardium
edule, and Tellina balthica. To these may be added
several kinds of Crustacea and Hydrozoa. Multitudes
of young M. arenaria may be seen in the Loch of S tennis,
about 5 miles from Stromness in the Orkneys, attached
bv bvssal threads to the under side of loose stones :
Neritina fluviatilis lives with them and deposits its
spawn on the same stones. Full-grown individuals of
the Mya are found (with Littorina obtusata) in the
lower part of the loch, which is open to the sea. The
fry are squarish-oval, decidedly inequivalve, and not
unlike Corbulae. My finest specimen is 3 inches by 5.
Lapland seems to produce much larger.

Gould considers the M. mercenaria and M. acuta of
Say synonyms of the present species.

2. M. trunca'ta*, Linne.

St. truncata, Linn. S. N. p. 1112 ; P. & H. i. p. 163, pi. x. f. 1-3, and (ani-
mal) pi. H. f. 1.

Body somewhat elongated and compressed, pale brown :
tubes very long ; tentacular filaments alternately large and

* Lopped.

MYA. 67

small, marked with a brown spot at the base of each ; valve
of excurrent tube conspicuous : gills pale brown, their points
entering the lower tube : palps large, excessively thin, and
rather sharp- pointed : foot narrow and straight, yellowish-
white.

Shell oval, less inequivalve than M. arenaria, nearly equi-
lateral, gaping widely at the posterior end but very little at
the anterior end, rather convex (especially towards the beaks),
solid, opaque, and lustreless : sculpture as in the last species :
colour greyish- white, with often a yellow or ochreous tinge:
epidermis rather thick, irregularly wrinkled or puckered, and
minutely striated in a transverse direction : margins rounded
on the anterior side, nearly straight in front, and truncated
on the posterior side ; dorsal margins sloping equally on both
sides : beaks small, sharp -pointed and inflected, more or less
contiguous, and sometimes abraded by mutual pressure : car-
tilage, hinge-line, and hinge-plate as in M. arenaria ; but the
hinge-plate is narrower : teeth, in the right valve an oblique
spur-like cardinal, which is more conspicuous in young and
immature specimens ; in the left valve a nearly upright trian-
gular plate, with a central cavity for the cartilage and a ridge-
like process or wall on the posterior side ; this plate is not so
large as in M. arenaria, compared with the size of the shell :
inside chalky-white, but occasionally nacreous and exhibiting
a few minute pearls within the pallial line : scars strongly
marked. L. 2. B. 2-65.

Yar. abbreviata. Shell not so broad, abruptly truncated at
the posterior end.

Habitat : Littoral in muddy gravel and sand ; but
frequenting more the open sea than M. arenaria.
It is sometimes found at considerable depths : I
dredged a young live specimen of the variety on the
Antrim coast in 80 f. about 10 miles from land. This
variety has also been taken by Professor King on the
Dogger bank, and by Mr. Barlee in Shetland. M.
truncata occurs in every upper pliocene bed, including
Moel Tryfaen (Darbishire) ; boulder-clay at Wick,
Whitby, and Scarborough (Peach, J. G. J., and Leck-
enby) ; Sussex raised beach (Godwin-Austen) ; Norwich,

68 MYID.E.

Red and Coralline Crag (Wood) . It is dug up in suck
quantities on a farm near the Crinan Canal, as to
be carted and used for manure. " At Lochgilphead the
syphon is preserved in the clay filling the interior
of the shell "■ (Geikie) . I have also seen specimens in
situ at Tufvoe near Gottenburg, about 200 feet above
the present level of the sea. In clay near Palermo
(Philippi) ; glacial deposits throughout Scandinavia;
"aldre leer" at Christiania, 90-470 feet (Sars) ;
Hudson's Bay (Drexler) ; Canada (Bell). Its foreign
range in a living state extends from Spitzbergen
(Phipps) and Kamtschatka (Steller), to the Black Sea
(Siemascho) , but probably subfossil in the last locality,
as Middendorff believed ; Misquer in lower Brittany
(Cailliaud) ; Quiberon (Hemon) ; Bay of Biscay (Au-
capitaine), in the old world : from Greenland (Scoresby
and others) to Massachusetts (Gould) , and Vancouver's
Island (P. Carpenter) in the new world. It is possible
that M. truncata may serve as a link in the chain of
evidence to support the hypothesis of Professor linger,
that Europe was once connected with North America
through the space now represented by the Atlantic
Isles. Olivi enumerated it as an Adriatic species, and
even gave a short description which leaves no doubt of
its being our shell ; but he may not have had recent
specimens. The same remark applies also to Brocchi's
statement, repeated by Bisso, that it is found on the
shores of Tuscany. The M. truncata of Chiereghini
from the Adriatic has been identified by Nardo with
Thracia papyracea. On the Scandinavian coast its ba-
thymetrical limits lie between low-water mark and 100 f.
Its vernacular name is "smyrsling" in Iceland,
" smirslingur " in the Faroe Isles, and "smirslin" in
Shetland and the west of Scotland, all these being evi-

MYA. 69

dently derived from the Danish word " smor," or butter,
which is expressive of the rich flavour of the animal. It
is eaten and much esteemed not only by the natives of
all northern countries, but by the walrus, arctic fox, and
the grey-headed duck or King Eider in Greenland ; and
there, according to Fabricius, the shell is sometimes used
as a spoon. Torell informs me that when he was last
at Spitzbergen he took from the stomach of a walrus,
that had been recently killed, a great number of the
feet of M. truncate, the other parts having been appa-
rently digested or got rid of. He is of opinion that the
walrus rakes up the My a from the mud by means of its
long tusks, and that, after crushing the shell between
its molar teeth, it spits out the fragments, as well as the
leathery tube. The cod on the North-American fishing"-
banks seem to be equally fond of this mollusk ; but it is
not so easy to say how they procure it. M. truncata is
often buried from 8 to 10 inches below the sea-bottom •
and it does not seem to be capable of changing its habi-
tation. The young occasionally occupy the deserted
holes of Saxicavae. They are more active than their
parents, and exhibit a remarkable precocity of instinct.
In Mr. Osier's well-known paper " On Burrowing and
Boring Marine Animals" (Phil. Trans. 1826) he says,
"On examining a My a truncata, dug up on the pre-
ceding day, and which, when grown, will not attempt
to burrow, I found two young ones, entangled in the
cuticle at the extremity of the syphon, scarcely more
than a line in length, and apparently but just excluded.
Being placed on sand in a glass of sea-water they buried
themselves immediately." In this and a later stage of
growth the shell has a distinct keel on the posterior
angle ; the beaks are calyciform and resemble a Kellia,
so that the fry must be of that shape. The half-grown

70 MYID.E.

shell is wedge-like on the longer side, with the terminal
edges reflected outwards : until it arrives at maturity
the truncation is incomplete. This alteration of shape
is not caused by absorption, but by the formation of
additional layers in front, which make the shell propor-
tionally longer or deeper than it previously was. The
Arctic variety, to which Forbes gave the name of Udde-
vallensis, is the usual form in glacial deposits ; it is
more depressed in the middle, obliquely truncated in-
wards, and excavated at the posterior end, frequently
to so great an extent, and in such a fashion, as if there
were cut

"A huge half-moon, a monstrous cantle out."

The internal structure of the shell is distinctly seen in
fossil specimens of this variety which have been perfo-
rated by the Cliona. A section thus exposed shows at
least 18 layers, and is unequally eroded, so as to re-
semble in miniature a perpendicular rock of oolite with
caverns at its base. A specimen of an intermediate
form, which I lately dredged in Dourie voe, Shetland,
measures 3| inches in breadth, and is of proportionate
length.

Petiver called this shell " The broad Pholade-muscle";
when half-grown it is the M. ovalis of Turton, and M.
pullus of S. Wood; the young is the Sphenia Sivainsoni
of Turton, and M. Swainsonii of Loven.

3. M. Binghami"*, Turton.

Schema Binghami. Turt. Dith. p. 36, t. 3. f. 4, 5, and 1. 19. f. 3. Sphamia
Binghami, F. & II. i. p. 190, pi. is. f. 1-3, and (animal) pi. T. f. 3.

Body elongated and compressed, pale yellowish-white : tubes
short, especially the incurrent one ; mouth of each encircled
by 5-10 rough white cirri ; valve of excretal tube large and

* Named after the late Lieut. -General Bingham, an assiduous collector
of British shells.

MYA. 71

very long, subhyaline, and delicately frosted : gills pale brown ;
lower one of each pair much larger than the other, lying hori-
zontally, and obliquely overlapped by the upper one : palps
somewhat triangular and pointed : foot small, narrow, subcy-
lindrical, of a bluish transparent hue ; it produces a byssus of
a few coarse filaments.

Shell wedge-shaped, decidedly inequivalve and inequi-
lateral, gaping at the posterior end, but not to the same extent
as the young of M. truncata, compressed, rather solid, opaque,
and somewhat glossy : sculpture, numerous fine but irregular
concentric strise, and occasional stronger marks of growth :
colour milk-white under the epidermis, which has a brownish-
yellow cast, and is often strongly wrinkled on the posterior
side, and extends over part of the pallial sheath : margins
obliquely truncated on the anterior side, usually straight in
front, and narrowing to an abrupt and straight edge on the
posterior side; this latter part has in each valve a blunt angle
or keel running diagonally from the beak to the lower point
of the posterior extremity ; dorsal margins extremely short on
the anterior side, long and mostly straight (although sloping)
on the opposite side : beaks small, incurved, not contiguous :
cartilage yellowish-brown : hinge-line slightly curved : hinge-
plate narrow : teeth, in the right valve a small and blunt but
distinct cardinal, besides the cartilage -pit, which is placed as
usual in this genus ; in the left valve the erect triangular tooth
is flatter and less elevated than in the preceding two species,
and considerably elongated on the posterior side : inside por-
cellanous : muscular scars extremely large, and placed near the
edges of the shell. L. 0-25. B. 0-5.

Yar. elongata. Shell considerably broader in proportion to
its length, which is nearly equal throughout and gives a cylin-
drical appearance ; posterior dorsal margin sometimes concave
and turned up at the extremity.

Habitat : In the cavities of limestone rocks and old
oyster-shells perforated by Saxicava rugosa and Cliona
celata, as well as among the roots or bases of Laminaria
saccharina, and in other places of shelter and conceal-
ment ; Channel Isles northward to Scarborough (Bean)
and Skye (Barlee), and all the coast of Ireland, in
5-25 f. The variety is found in the deserted cases of

72 SAXICAVID.E.

Serpula triquetra at Guernsey, Lulworth, and other
places. Coralline Crag (coll. S. Wood). Its extra-
British localities are the Boulonnais (Bouchard-Chan -
tereanx) ; Croisic in lower Brittany (Cailliaud) ; coast
of Spain (M' Andrew) ; Gulf of Lyons (Martin) ;
Cannes (Mace) ; Spezzia (J. G. J.) ; and Tunis, in 25 f.
(M 'Andrew) .

M. Binghami does not appear to have the power of
excavating stones or shells, because specimens thus en-
closed are frequently distorted or constricted, so as to
fit the holes which they occupy. Its habits in this
respect are the same as those of Tapes pullastra var.
perforans, Thracia distorta, and some other bivalves.
My largest specimen is scarcely three-quarters of an
inch in breadth • but the late Dr. Lukis obtained much
larger ones from the cavities left by Saxicava at
Guernsey. It differs from M. truncata of the same
size in being more inequivalve, inequilateral, and com-
pressed; in the anterior side being invariably and ab-
ruptly truncated, instead of rounded ; in the posterior
extremity being more straight, and having a smaller
gape; in that side being distinctly angulated, espe-
cially in the left valve ; and the tooth in the left valve
is less raised. It, however, belongs unquestionably to
the same genus.

Family XXI. SAXICA'VID.E, Swainson.

Body oval or oblong: mantle thick: tubes more or less
united ; orifices fringed with cirri : gills unequal on each side :
palps triangular : foot finger-shaped, occasionally byssiferous.

Shell rhomboidal, more or less inequilateral, and in the
genus Saxicava sometimes inequivalve, always gaping at the
posterior end (where it is obliquely truncated), and sometimes

SAXICAVIDjE. id

also towards the other end : epidermis membranous : beaks
usually separate, not projecting, turned towards the anterior
side : ligament external : hinge strong, furnished with cardinal
teeth, which are in some cases small, indistinct, or obliterated,
and an upright ledge to support the ligament: pallial scar
placed far inside, and having a broad sinus : muscular scars
large and conspicuous.

A family having close affinities with the last, but
different in possessing an external ligament instead of an
internal cartilage, and in the consequent structure and
apparatus of the hinge. Some burrow in sand or mud
like Myce ; others perforate certain rocks and hard
substances, to a depth equal to the breadth of the shell
and length of the tubes when fully extended. The
mode by which these various objects are effected appears
to be the same in every case, viz. by the propulsion or
attrition of the muscular foot, which is always placed
near the posterior end of the shell, assuming when in
action the form of a cone or disk, and occupying the
space to be excavated. Having already discussed at
some length the latter part of the subject in the intro-
duction to the first volume, I will not here say more
than that occasional notices of this remarkable operation
will be found in subsequent pages, while treating of par-
ticular genera and species comprised in the Lamarckian
group of " Lithophages," as well as of the Teredines.
Most of the Suxicavidce pass their lives in a hermit-like
seclusion, each immured in its own cell, content with the
food brought by the waves or minute currents produced
by the siphonal cilia, as well as with a certain degree of
immunity from outward foes. Having no means of mutual
intercourse, the nature of their sexual organization maybe
easily inferred ; and the analogy in this respect between
them and many flowering plants, which are rooted to the
soil, cannot be very remote. Individuals of the same

VOL. III. E

74 saxxcavid^:.

species of Saocicava which excavates holes in calcareous
rocks or sandstone will, failing such materials, or for
other reasons which are at present unknown to us, spin
a bvssus and thus fix themselves in the chinks and cran-
nies of harder rocks, or now and then inside old bivalve
shells.

Genus I. PANOPE'A*, Menard de la Groye.

PL III. f. 2.

Body oval, fleshy : tubes very long, united nearly through-
out, and enclosed in a tough leathery sheath : gills long : foot
short, stout and muscular.

Shell equivalve, wrinkled transversely, gaping widely at
both ends but much more so at the posterior end : epidermis
thin: ligament short, prominent, attached to a process of the
hinge-plate, which extends as the shell increases in size, and
is sometimes triangular or represents the arc of a circle : tooth,
a small conical cardinal in the right valve fitting into a cavity
in the left valve : pattial scar entire, not deeply sinuated.

Most British conchologists are better acquainted with
the large and scarce shell usually known as "Panopcea
Norvegica " (but which, as I have before remarked, is a
species of Saxicava), than with the small shell which I
consider a true Panopea. Although the animal of this
latter species is as yet unknown, the peculiar form of
the shell, the structure of the hinge, and the pallial scar
present the same characters which belong to P. glyci-
meris (or Aldrovandi) and its numerous congeners.
The animal of P. australis was described by Valen-
ciennes in the ' Archives du Museum d'Histoire natu-
relle ' for 1839, and that of P. glycimeris by Woodward
in the i Proceedings of the Zoological Society ■ for 1855.
The former likened it to that of My a arenaria, and was
of opinion that the labial palps are olfactory organs.

* A Sea-Nymph.

PANOPEA. / .)

But neither of these zoologists appears to have seen it
alive. A great many species are known, both recent
and fossil, some of the latter being Oolitic, and others
(according to D'Orbigny) Permian.

The name of this genus has been spelt in various ways.
Besides the original and correct one which I have given,
Goldfuss and others called it Panopcea, Swainson Pano-
pia, and Nyst Panopcea. P. glycymeris is the type of
Klein's genus Glicimeris, which name has precedence
of Panopea by more than half a century ; but Glycimeris
is now used for another well known genus.

Panopea plica'ta*, Montagu.

Mytihisplicatus, Mont. Test. Brit. Suppl, p. 70. Saxicava rugosa, young?.
F. & H. i. p. 149, pi. vi. f. 1-3, and app. iv. p. 248.

Shell rhomboidal, considerably dilated towards the posterior
end (where the gape is very long, although not much wider
than that of the anterior side), compressed, especially in front.
thin, of a nacreous texture, semitransparent, and somewhat
glossy : sculpture, numerons fine but irregular concentric stria?
or plaits, and the surface in perfect specimens is minutely and
partially granulated : colour milk-white : epidermis extremely
thin, pale yellowish-white : margins rounded on the anterior
side, nearly straight in front, expanding and arched (although
obliquely truncated) on the posterior side, and forming a high
shoulder at the back, with a distinct but blunt keel or ridge
from the beak to the lower angle ; anterior dorsal margin very
short : beaks small, slightly inflected and calyciform as in
My a Binghami : ligament yellowish-brown: hinge-line nearlv
straight : hinge-plate rather narrow but reflected, and forming
in the left valve a slight groove on the outside ; it is furnished
with a triangular process for the ligament, which slants a little
inwards obliquely, like the tooth or cartilage-pit in Mya ; this
process varies in position, as well as in shape and size : tooth
very minute, and not always present : inside porcellanous, and
somewhat iridescent : pallial scar very distinct, with a shallow
sinus: muscular scars irregularly triangular. L. 0*25. B. 0-4.

Habitat : Skye (Laskey) ; among trawl refuse from

* Plaited.

E 2

76 SAXICAVID^E.

Plymouth, and dredged in muddy sand off Skye, and in
the voes of Deal, Dourie, and Basta, Shetland, at depths
ranging from 5 to 40 f. (J. G. J.) ; small living speci-
mens were also dredged by Mr. Barlee in Loch Fyne,
and single valves by Mr. Hanley near the pier at Hyde
in the Isle of Wight; Moray firth (Dawson) ; Stone-
haven (Macgillivray) ; Walton-on-the-Naze (S. Wood).
It is a common shell in the Coralline Crag at Sutton ;
and Nyst found it in the corresponding formation near
Antwerp. M f Andrew dredged it in 40 f. off Gibraltar
and in Vigo Bay, Lilljeborg in 70 f. at Bergen; and it
has also been found at Hellebsek in Zealand.

I hope the animal will at some future time be made
known. The shell may be distinguished from My a
Binahami bv its nacreous texture, the extreme dilatation
of the posterior side, and having a ligament instead of
a cartilage, with a different hinge. Some specimens
are partially incrusted by a mineral or faecal deposit,
showing the sedentary or inactive habits of the animal.
The largest in my cabinet is nearly half an inch broad.
Fossil specimens are rather more oblong, and the pos-
terior dorsal margin is straighter and less arched than
in recent specimens.

If the present species, or my description of it, is com-
pared with Montagu's account, and with the figure
given by the original discoverer, Laskey, in the ' Me-
moirs of the Wernerian Society' (vol. i. pi. viii. f. 2),
their identity will, I think, be found undeniable. It is the
Sphenia cylindrica of S. Wood, and Saxicava fragilis?
of Nyst. The Mytilus carinatus of Brocchi may possibly
be a variety. Philippi proposed for this last and another
species the generic name Arcinella, which had been
previously used by Oken and Schumacher for two other
kinds of bivalve shells.

SAXICAVA. 77

The evidence that P. glycimeris has been found in
our seas is not satisfactory; this species inhabits the
Lusitanian and Mediterranean coasts.

Genus II. SAXI'CAVA*, Fleurian de Bellevue.

PI. III. f. 3.

Body muscular : tubes extensile, diverging at their extremi-
ties, and covered by a leathery or membranous sheath : gills
prolonged into the cavity of the branchial tube : foot furnished
with a byssal groove.

Shell often inequivalve, wrinkled transversely, gaping at
the posterior end, and sometimes also in front (or what may
be termed the antico -ventral part) : epidermis thick : ligament
short, prominent, attached to an elongated process of the
hinge-plate : teeth, a small conical cardinal in the right valve,
locking between two similar ones in the left, but frequently
obsolete or wanting : pallial sear interrupted or broken up
into separate spots, not deeply sinuated.

The doubtful position which this genus formerly occu-
pied among bivalve shells appears from the circumstance
that Linne called the typical species (S. rugosa) and its
variety arctica respectively Mytilus and Solen, Fabricius
Mya, Strom Chama, Poli Donax, Solancler Venus, Bru-
guiere Cardita, and Turton Anatina ; and that the variety
constituted the genera Hiatella of Daudin, Clot ho of Faujas
St. Fond, Byssomya of Cuvier, Byssonia, Rhombus, and
Rhomboides of De Blainville, Didonta of Schumacher,
Biapholius, Coramya, and Pholeobia of Leach, and Agina
of Turton. Grav makes Hiatella and Saxicava distinct
genera. The former name was published in 1799, and
the latter in 1802 ; but Daudin did not sufficiently
characterize his genus, and Saxicava may be considered
as now established by general usage. According to
Chenu the geological age of the present genus dates from

* Rock-perforator.

78 SAXICAVID.E.

the Jurassic epoch; Searles Wood, however, believes
that it was not born before the tertiary formation.

1. Saxicava Norve'gica*, Spengler.

My a norvegica, Spengl. Skrivt. Nat. Selsk. iii. (1). p. 46, t. ii. f. 18.
Panopcsa Norvegica, F. & H. i. p. 174, and app. iv. p. 249, pi. xi. and
(animal) pi. W. f. 1.

Body oblong, pale pinkish drab : mantle covered with a black
skin : tubes protected by a dark-brown leathery sbeath, some-
what unequal in length, the upper or excretal tube being the
shorter and smaller of the two ; orifice of the larger tube
encircled by 30-40 short tentacular cirri, of a brick-red
colour, alternately large and small, and sometimes folded back
on the edges of that tube ; the smaller tube is also fringed, but
much less distinctly : gills irregularly pectinated : palps long,
delicate, slender and pointed, united around the mouth : foot
very small when contracted : liver green.

Shell oval with a somewhat oblique and irregular outline,
the right valve a trifle larger than the left, moderately convex;
it has a broad furrow in the middle gradually enlarging towards
the front, a considerable gape between that part and the
anterior side, and a remarkably large and wide opening at the
posterior end ; it is thick, opaque, and lustreless : sculpture,
coarse, distant, and irregular concentric wrinkles: colour whitish,
occasionally stained with a ferruginous tinge : epidermis pale
yellowish -white, puckered in every direction, not continued
over the tubular sheath, which is of a fibrous nature : margins
rounded or obtusely angular on the anterior side, nearly straight
or slightly incurved in front, obliquely truncated on the pos-
terior side, and a little reflected outwards in adult examples ;
dorsal edges sloping gradually on each side, the posterior one
being usually more than twice the length of the other : beaks
blunt and much inflected: ligament large, horncolour : hinge-
line almost straight : hinge-plate broad and thick, excavated
for the reception of the teeth, and furnished with a short but
solid process for the ligament, which is reflected outwards and
callous in younger shells : teeth, in the right valve a compara-
tively minute cardinal, and in the left valve two others of even
a smaller size, which are placed so near together as scarcely
to allow space for receiving between them the opposite tooth :

* Norwegian.

SAXICAVA. 79

inside whitish, with a faint iridescent hue in certain parts :
pallia! scar exhibiting about a dozen spots of different sizes :
muscular scars deep ; anterior triangular or semioval, posterior
elongated. L. 2. B. 3.

Habitat : The Dogger bank, off the coasts of York-
shire, Northumberland, and Durham, deeply imbedded
in muddy ground at about 30 f. j and Mr. M' Andrew
dredged a valve in 82 f. east of Shetland. It is very
difficult to procure, and is consequently scarce. Fossil
in most of our newer tertiaries up to the Red Crag : at
Chillesford it is found in pairs (Woodward), and at
Wick in a fragmentary state in the boulder-clay (Peach) j
raised beach at Moel Tryfaen (W. Drury Lowe) ; tole-
rably common in the Clyde district; Palermo, in clay
(Philippi) ; near Christiania in the older part of the
glacial formation at 460 feet, and in the younger or
post-glacial group at 60-100 feet above the sea-level
(Sars) ; Greenland (Rink) . Recent in Iceland (Steen-
strup) ; Finmark, 68° 45' (Blix) ; Drontheim (Spengler) ;
Cattegat (Loven) ; Bohuslan (Malm) ; Hellebsek in
Zealand (Mus. Copenhagen); White Sea (Lamarck);
Coasts of Russian Lapland (Baer and Middendorff) ; Sea
of Ochotsk (Middendorff) ; Newfoundland fishing-banks
(Gould) ; Labrador (Mighels) ; New England (Stimpson) .

This is probably the strange shell which Donovan in
1802 noticed as having been "fished up between the
Dogger bank and the eastern coast of England''; but
his knowledge of it appears to have been derived from
hearsay, and he mistook Panopea glycimeris for the pre-
sent species, The first reliable announcement of its
being British was made by Doctor Turton in the ' Zoolo-
gical Journal' for 1826 on Mr. Bean's authority, with
the addition that a single valve had also been found on
Aberlady sands in the south of Scotland. Mr. Bean's

80 SAXICAVID.E.

relation of the circumstances connected with his dis-
covery is amusing. He says, " To some of the fishermen
of our coast it is well known by the name of the ' bacca-
box/ from a fancied resemblance to one of their most
useful household gods. All the specimens [which he ob-
tained] were rescued from destruction in a singular
manner. The first was destined for a tobacco-box ; the
second had the honour of holding the grease belonging
to the boat establishment ; and the third — ' Tell it not
in Gath, publish it not in the streets of Askalon ' — was
inspected alive for several days by the officers and mem-
bers of a modern philosophical Society (all of them
unconscious of its value), and after amusing them by
squirting water to the ceiling, was at last seen by a
learned friend, purchased for a trifle, and generously
placed in our cabinet.- The long-line fishermen, every
now and then, capture living specimens, by means of
their hooks becoming fixed in the tough leathery sheaths
of these enormous Saxicavce ; and thev thus increase
not a little their precarious earnings. The shell is much
sought after by collectors, and is never likely to be so
plentiful in their repositories as it evidently is in that
of Nature — unless some adventurous zoologist, like
Milne-Edwards or the unfortunate Barrett, should be
tempted and able to explore, with the aid of a diving
helmet or dress, the comparatively deep sea-bottom in-
habited by these mollusks. Dr. Mighels says that the
specimens which he obtained were taken from the sto-
machs of cod fishes. S. Norvegica is gregarious, and
lives in company with Mytilus modiolus, whose byssal
fibres may be occasionally seen adhering to the shell of
the present species. Sessile Foraminifera {Truncatulina
lobatula) may also be detected on the outside of the
tubular sheath, even at its base, showing that this part

SAXICAVA.

81

is habitually left exposed, and not merely protruded at
rare intervals. No portion of this appendage can be
withdrawn into the shell; and the same is often the
case also with S. rugosa. The structure of the shell
must be cellular, because in fossil specimens the surface
when abraded or worn appears under the microscope to
be studded with circular pits. As Spengler well re-
marked, the shell is not unlike My a truncata, especially
in the large opening at the posterior end. Clark pointed
out its close relation to Saxicava, and Woodward has
satisfactorily ascertained and shown its generic place.

It is the Glycimeris arctica of Lamarck, Panopcea
Spengleri of Valenciennes, P. Bivonae of Philippi, and
P. Middendorffii of A. Adams.

2. S. rugo'sa*, Linne.

Mytilus rugosus, Linn. S. N. p. 1156. S. rugosa, F.&H. i. p. 14G, pi. vi.
f. 7, 8, and (animal) pi. F. f. 6.

Body varying in shape from oval to cylindrical, greyish-
white more or less tinged with yellow, sometimes brownish-
vellow or orange : mantle very thick, coarsely and deeply
wrinkled : tubes very extensile, enclosed in a brown membra-
nous sheath to within a short distance from their extremities,
where they separate and slightly diverge ; orifices often pinkish,
fringed with a double row of short whitish cirri with trun-
cated points ; each tube has from 16 to 20; those in the outer
row are much smaller than the inside ones ; excretal valve
bell-shaped, widely open : gills very narrow : palps small : foot
finger-shaped, rather long, extremely flexible and muscular.

Shell oblong, usually somewhat inequivalve but especially
in its free and younger state, slightly compressed except
towards the beaks, frequently gaping in the front or on the
antico- ventral side, as well as at the posterior end, thick,
opaque and lustreless : sculpture, coarse, distant, and irregular
concentric wrinkles ; the posterior side is marked in young
and free specimens by a double ridge, which is usually spinous
or imbricated, and diverges from the beak in each valve

* Wrinkled.

E 5

82 saxicavid^e.

towards the siphonal extremity : colour whitish : epidermis
light brownish-yellow, more or less puckered : margins rounded
on the anterior side, nearly straight in front, either curved or
bluntly truncated on the posterior side ; dorsal edges gently
sloping on each side, the posterior one being three or four
times as long as the other : beaks small and blunt, inflected,
and inclining considerably to the anterior side : ligament yel-
lowish-brown, proportionally longer than in the last species :
hinge-line slightly curved : hinge-plate broad and thick, exca-
vated externally to receive the ligament, so as to form in some
specimens an elongated ledge or process, which is reflected
outwards and callous in younger shells ; it is occasionally also
excavated (but slightly) internally : teeth often wanting ; but
when they occur, the right valve has a very small erect car-
dinal, closely interlocking between two others in the left valve :
inside porcelain- white and glossy : pallial scar exhibiting in
dead and fossil specimens a few spots of different sizes, which
are indistinct in fresh specimens : muscular scar's more con-
spicuous, triangular. L. 0*6. B. 1-4.

Var. 1. arctica. Shell more angular, and having distinct
ridges ; beaks less worn ; teeth usually more developed : this
variety never burrows in stone, but is attached by a byssus.
My a arctica, Linn. S. N. p. 1113. S. arctica, F. & H. i. p. 141,
pi. vi. f. 4-6.

Var. 2. minuta. Shell smaller, and having prickly ridges :
this is the younger or immature state of the first variety.
Solen minutus, Linn. S. N. p. 1115.

Var. 3. prmcisa. Shell smaller, abruptly truncated close to
the beaks at the anterior end. Mytilus prcecisus, Mont. Test.
Brit. p. 165, t. 4. f. 2.

Var. 4. pholadis. Shell gaping widely in front, and wedge-
shaped. Mytilus pholadis, Linn. Mant. Plant, p. 548.

Habitat : On every part of our coast, from the Shet-
land to the Channel Isles, where there is limestone,
chalk, or new-red sandstone, all of which this species
excavates. It usually inhabits the lowest verge of spring-
tides, and the Laminarian zone; but Mr. Peach pro-
cured live specimens from a rock perforated by them in

SA XI CAVA. 83

30 fathoms, 4 or 5 miles off the Deadman in Cornwall ;
and a piece of primitive limestone similarly excavated
was brought to me by a fisherman, having been hooked
up from more than twice that depth about 30 miles
eastward of the Whalsev Skerries in Shetland. Vars.
1 and 2. Universallv diffused from low-water mark to
145 f. (Beechey) . Var. 3. Confined in narrow crevices
of rocks, and beneath the hinges of old bivalves. Var.
4. In siliceous limestone. This very common species
is found everywhere in upper tertiary strata, as far back
in time as the Coralline Crag, and it frequently denotes
arctic conditions. Glacial formation at Christiania,
50-470 feet (Sars) ; Subapennine and Sicilian beds
(Brocchi and Philippi); Antwerp (Nyst); newer mio-
cene near Antibes (Mace). The extent of its geogra-
phical range is almost unparalleled in the history of the
Mollnsca. It appears to have spread over the greater
part of the globe, from one pole to the other. I cannot
distinguish Australian from Greenland specimens by
any character except that of size, those from the north
being much larger.

The animal was well described by Fabricius. He said
that it was cooked and eaten bv the Greenlanders, and
that on being touched or alarmed it squirts out water
and contracts itself like an Ascidia. He found the
variety pholadis with other shell-fish from deepish water
in the crop of the King Eider-duck. The fact of its
being byssiferous of course did not escape his notice,
and it has been since mentioned by Mr. Osier and Mr.
West. It is equally notorious that trias or new-red
sandstone (which is not calcareous) as well as limestone,
is perforated by the typical form. I can fully corrobo-
rate Mr. Clark's observations on this point. Lister
noticed nearly two centuries ago that the holes are con-

84 SAX1CAVID.E.

siderably larger than these shell-fish require in order
that they may freely open their valves. This gives
room for the foot to expand and work. The side
of the shell in all such cases is often more or less
rubbed or worn, in the same way as the spinous
fringes of Pholas dactylus, in which the last-formed
rows are uninjured; and the epidermis is seldom pre-
served on that part. In specimens of the typical form
of S. rugosa, excavating limestone in Shetland, the
ventral and exposed border of the mantle has sometimes
delicate sessile Foraminifera (Truncatulina lobatula and
Discorbina globularis) living on it, which proves that the
mantle is not the organ of attrition. If an acid were em-
ployed by the Saxicava in dissolving calcareous rocks, it
would assuredly destroy that portion of the shell from
which the epidermis had been removed, as well as the
shells of the Foraminifera. The edges of the excavation
are sharply defined, and present an appearance very un-
like that which would be produced by a solvent action.
Therefore, either the shell or the foot must be the opera-
tive agent. Were it the former, the epidermis in front
would be entirely abraded; and such is never the case. The
Saxicava do not work, if they can meet with ready-made
holes. The late Dr. Lukis, in one of his letters to me,
said, " Successive generations will occupy the same hole.
The last inhabits the space between the valves of its
predecessor. In this way four or five pairs of shells may
be frequently seen nested one within the other, and not
unusually a Sphenia Binghami in the centre of all. v
Cailliaud observed a Saxicava within a specimen of Vene-
rupis Irus, which it had perforated. Malm found a cylin-
drical variety in the burrows of Limnoria lignorum. The
form of the shell is so variable and dependent on habitat,
that (as the late M. Bouchard-Chantereaux remarked)

VEXERUPIS. 85

it is possible to discover almost as many species as indi-
viduals. I am sorry to differ from Turton and the
authors of the ' British Mollusca'; but I do not believe
S. arctica to be a distinct species. The characters given,
in the same terms, by these writers, are equally applica-
ble to both forms. The " lunule-like excavation in front
of the beaks " arises from the anterior side being more
contracted than the other. Specimens enclosed in stone
are generally symmetrical, and less angular than those
which are free or attached by a byssus. The present
species differs from S. Norvegica in being oblong instead
of oval, not having a wide furrow in front, gaping much
less at the posterior end, and in being furnished with a
double ridge, which is often serrated in young individuals.
It is, besides, comparatively a dwarf.

It would be tedious and unnecessary to particularize
all the synonyms. I have collated seventeen, the spe-
cific names of which are different, in addition to those
quoted above in describing the principal varieties.

Genus III. VENERU'PIS* Lamarck. PL III. f. 4.

Body oblong, thick : mantle bilobed : tubes united for about
two-thirds of their length, naked ; longer cirri pinnate : gills
and palps small: foot compressed, byssiferous.

Shell eqnivalve, cancellated : ligament elongated, and sunk
within the dorsal margins : teeth, 3 in one valve, and 2 or 3 in
the other : pallial scar rather deeply sinuated.

Although the shell described by Lamarck as the type
of Venerupis is Tapes pullastra var. perforans, the cha-
racters by which he defined the genus are sufficiently
comprehensive to apply also to V. Irus, which he in-
cluded in it. There is undoubtedly a great similarity

* Koek-Venus ; per syncopen for Venerirupis.

86 SAXICAVID^K.

of shape between this genus and Tapes; but the shell
of Venerupis is regularly cancellated, while that of Tapes
is nearly smooth or marked only by concentric flattened
ribs and obscure or microscopical longitudinal striae.
Perhaps Venerupis is here scarcely in its place. It is
impossible to make a linear or graduating arrangement.
An oak tree in the course of its growth will have many
interlacing boughs, and will spread out : so with the
system of natural history in passing through successive
stages of development. The Venerupes occupy holes
made by Saxicava, or attach themselves by byssal
threads to rocks and other substances. The genus does
not claim a greater antiquity than the miocene period.

Venerupis Irus*, Linne.

Donax Irus, Linn. S. N. p. 1128. V. irus, F. & H. i. p. 156, pi. vii. f. 1-3,
and (animal) pi. G. f. 2.

Body white with a pinkish tinge : tubes slender, unequal in
length, pellucid, speckled with flake-white, diverging near the
extremities, which are of a pink colour ; longer cirri of the
orifice erect and feathered, shorter ones reflected and plain ;
retractile valve of excretal tube conspicuous.

Shell oblong, compressed, slightly gaping at the posterior
end but in no other part, solid, opaque, and usually lustre-
less : sculpture, 15-20 thin laminar concentric ridges, which
become broader and foliaceous towards each end of the shell ;
these ridges and their interstices are crossed by numerous fine
longitudinal striae, radiating from the beaks ; the surface is
also covered with minute close-set transverse striae : colour
pale yellowish-white, with sometimes (especially in the young)
a stain of reddish-brown or purple on the umbonal area and
posterior side : epidermis thin and seldom visible : margins
rounded or obtusely angular on the anterior side, usually
straight in front, truncated or wedge-shaped on the posterior
side, which is at least twice as large as the opposite side, more
or less straight behind, with an abrupt slope from the beaks

* The name of a beggar in the Odyssey.

VENERUPIS. 87

to the anterior end, so that the posterior dorsal margin occupies
nearly one side of a parallelogram : beaks small, inflected, and
inclining considerably to the anterior side : ligament yellowish-
brown or homcolour, contained in a groove or excavation
with shelving sides, which extends for some distance from the
beaks : hinge-line obtuse-angled : hinge-plate thick and broad :
teeth erect, placed on the anterior dorsal line, the outermost
and innermost diverging ; in the right valve 3, of which the
outside one is much smaller than the other two, and these are
cloven ; in the left valve are also 3 similarly arranged, the
innermost being the smallest : inside porcellanous, often par-
tially stained with reddish-brown, particularly the hinge-plate
and posterior side : pallia! scar uneven, with a tongue-shaped
sinus : muscular scars deep ; anterior roundish, posterior oval
and situate close to the margin at the lower angle. L. Oo.
B. 1.

Habitat : Laminarian zone on the coasts of Dorset,
Devon, Cornwall, Glamorgan, Pembroke, and Ireland
(west, sonth, and east). Red Crag (S.Wood); and
Philippi has recorded it from the South-Italian tertiaries.
It has not been noticed in Scotland or further north;
its southern distribution extends from Brittany to the
Adriatic, Black Sea, and yEgean, both sides of the
Mediterranean, and the Canary Isles, at depths ranging
from the shore to 20 f.

It is attached by a byssns to gneissic rocks in Con-
nemara (Parran), and to the roots of Laminar i a bulhosa
in the west of Ireland (Harvey) ; it occupies holes made
by Saxicava rugosa in new-red sandstone at Exmouth
(Clark), in limestone at Tenby (J. G. J.), and Cannes
(Mace) ; and it inhabits crevices of rocks (but never
perforates them) on the coast of Sicily (Philippi) . The
shell being frequently distorted shows that the Venerupis
is not a borer, but accommodates itself to any place of
shelter : when thus enclosed it is occasionally incrusted
with nullipore and Spirorbis granulatus. The very
young are square, and the fry nearly circular. In perfect

88 SAXICAVID.E.

specimens the laminar ridges are fringed and resemble
those of the lovely Venus lamellata. We learn from the
interesting experiments made by M. Beudant, as to the
capability of marine mollnsks living in fresh water, that
out of 20 individuals of V. Irus 16 remained alive at the
end of 22 days after the sea-water in which they were
placed had been gradually mixed with fresh, so as to
render the proportions equal, and that all the survivors
were instantly killed on being immersed in quite fresh
water. Of Mytilus edulis 30 individuals lived for 5
months in the admixture, and for 15 davs in fresh
water.

Its specific name may have been derived from the
ragged look of the shell, compared with that of its
original congeners, the Donaces. Irus was a common
beggar and messenger at Ithaca, who insulted Ulysses
in his own palace upon his return home incognito, and
was knocked down by him with a blow of his fist.
Among the Roman poets the name symbolized wretched
poverty and that reverse of fortune which Ovid expressed
in the following line,

" Irus et est subito, qui modo Croesus erat."

This characteristic shell is the Tellina Comubiensis of
Pennant, Cuneus foliatus of Da Costa, Venus cancellata
of Olivi (but not of Linne), and Venus Bottarii of
Renier.

I have a specimen of Venerupis Lajonkairii, Payrau-
deau ( V. decussata, Philippi) , which came from the col-
lection of Mr. George Humphreys, with the undermen-
tioned name and note of its locality, " Venus striata, H.
Rrighthelmstone W. H. 1768." It is a native of the
Mediterranean, and resembles the young of Tapes de-
cussatus ; but, besides the difference of hinge-structure,

GASTROCH.EXID.E. 89

it is beaded lengthwise, and has a more square outline
with rounded angles. Philippi calls it " rotundato-
quadrangula," a definition at which mathematicians
might be inclined to smile.

Family XXII. GASTKOCEUE'NIDjE, Gray.

Body oblong : mantle large and thick : tubes long, united
throughout ; orifices cirrous : gills unequal, prolonged into the
branchial tube : palps small, somewhat triangular and thick :
foot finger-shaped, sometimes byssiferous.

Shell enclosed in a testaceous flask-like case with a narrow
bipartite or divided neck ; it is oblong, equivalve, very inequi-
lateral, wedge-shaped and widely gaping in front ; anterior
end pointed : epidermis membranous : beaks nearly terminal :
ligament long, external : hinge straight, toothless but furnished
with a horizontal plate or shelf- like process : pallial scar broad,
and deeply sinuated : muscular scars strong.

This family connects the Saccicavida? and Pholadida.
Its smooth shell is not unlike that of S. rugosa var.
pholadis, which has also a ventral gape, and is most
frequently toothless ; although its reflected hinge-plate
and pointed anterior extremity remind us of P kolas
crispata. The foot is more characteristic of the first-
named family, and the pallial tubes of the latter. But
its distinctive and peculiar feature is the outer case or
covering, in which all the Gastrochamidce enwrap them-
selves on arriving at maturity. The body of this case
appears to be formed, like the shell, by a secretion of
the mantle ; and the enormous opening in front, between
the valves, must greatly facilitate the work. The animal
probably uses its flexible foot, turning it round on every
side, to mould the walls of the case. There can be no
doubt that the neck is elaborated by the siphons,

90 GASTROCH^NID.E.

in the same way that the Teredo makes the outer points
of its testaceous sheath. In Clavagella and Aspergillum
the valves are united with the case, being apparently
soldered to it. Mr. Try on has lately published a careful
monograph on the Order ' Pholadacea/ comprising the
present family, Pholadidce, and Teredinidce.

Genus GASTROCILE'NA* Spengler. PI. III. f. 5.

See the description of the family for that of the solitary
genus which inhabits the British seas.

Placed by Lamarck in his family Pholadaires. It
was included in the genus Uperotus of Guettard, Chama
of Retz, Fistulana of Bruguiere, and Trapezium of von
Miihlfeldt. Swainson erroneously spelt the name Gas-
trochina. Morch, H. and A. Adams, and Tryon con-
sider the G. mumia of Spengler (a tropical shell) the
type of the present genus, and refer the European
species to Fleurian de Bellevue's genus Rocellaria. The
only species which we possess excavates and encases
itself in limestone, new-red sandstone, and old shells ;
sometimes the case is found free, and incrusted with
fragments of shells and grains of sand. There can be
no question as to its perforating powers. The case is
occasionally lodged in the valve of a large Pecten maxi-
mus or Lutraria elliptica, half of it on one side of the
valve and half on the other. If an acid or chemical
menstruum were necessary for this operation, it would
either dissolve the calcareous matter of the envelope, or
not act on the uncalcareous sandstone. The shell is
invested by a delicate epidermis, which is more perfect
on the posterior or outer end, but is sometimes worn

* Gaping in the ventral part.

GASTROCH.ENA. 91

away in the line of excavation. Several exotic kinds
are known. One of these excavates coral, and when
full- grown encases itself; but the coral soon outgrows,
smothers, and completely envelopes the G astro chama.
Instinct seems in this case to be at fault. The Jurassic,
cretaceous, and tertiary formations contain many species.

Gastroch^ena dtj'bia*, Pennant.

Mya duhia, Penn. Br. Zool. iv. p. 82, t. 44. f. 19. 67. modiolina, F. & H. i.
p. 132, pi. ii. f. 5-8, and (animal) pi. F. f. 5.

Body club-shaped, pale brown with a reddish tinge : mantle
corrugated : tubes slender and transparent, capable of being
extended to three times the length of the shell ; terminal cirri
short, dark purplish -brown : gills narrow, and of a thin tex-
ture, finely pectinated on both surfaces : palps smooth without
and striated within : foot very expansible, conical when at
rest.

Shell elongated and obliquely twisted from the beaks to
the posterior end, so that its proportions and course of growth
are those of a Mytilus, convex, rather thin, opaque, and lustre-
less : sculpture, distinct but irregular concentric strise, which
are slightly imbricated in front : colour whitish : epidermis
yellowish- brown : margins narrow and acutely angular at the
anterior end, largely excavated in front (exhibiting an oval
gape), with a bold sweep towards the posterior side, which is
broad and obtusely angular ; dorsal margin on the latter side
long and high-shouldered or raised; anterior dorsal margin
extremely short and truncated : beaks blunt and inflected :
ligament semicylindrical, somewhat prominent, yellowish-
brown ; posterior end attenuated : hinge-line nearly straight :
hinge-plate rather broad, thin, and reflected outwards ; it is
thickened within, where it projects downwards, occasionally
resembling a large and blunt triangular tooth ; the anterior
edge is also callous : inside porcelain-white, glossy, and faintly
iridescent : pallial scar usually indistinct : muscular scars irre-
gular on the anterior side ; the posterior one is large and
triangular. L. 0*8. B. 0-35.

Var. ovalis. Shell shorter, broader, and thinner.

* Doubtful.

92 GASTRGCH^NID.*:.

Habitat : Southern coasts of England, the Channel
Isles, South Wales, Barmouth, and the south and west
of Ireland, in 8-20 f. The variety was found by Mr.
Clark at Exmouth. Red and Coralline Crag (S.Wood) ;
Italian tertiaries (Brocchi and Philip pi). It does not
appear to be a northern shell ; but it is tolerably
common on the coasts of France, Spain, Italy, Greece,
Algeria, Madeira, and the Canary Isles, at depths
between 2 and 60 f.

This remarkable shell, as well as its animal and case,
Avere described by Montagu with his wonted accuracy.
He states that he had specimens not only in limestone,
but in granite ; and he modestly observes, " How the
siliceous part of this last is destroyed, we do not pretend
to determine." Cailliaud has ascertained that all the
lithophagous bivalves secrete a corrosive liquid, at least
in the months of May and June ; and, not content with
the usual test of litmus-paper, he tasted some of the
animals — thus exemplifying the saying of Seneca (' De
vita beata'), " curiosum nobis natura ingenium dedit."
We are told by the French philosopher that the G astro -
chana affects the throat with an insufferably acrid flavour,
like that of a bitter cucumber. But the oyster, which
is not lithophagous, and Pholas are equally provided
with the same acid. This fact seems to militate against
the chemical theory. I have a cluster of a dozen
G. duhia in a single oyster-shell. The case or crypt is
thick and composed of a great many layers. The ex-
posed part of it is formed of tubercular concretions of
different shapes and sizes ; its neck resembles a double
cylinder joined together but open on the inner side,
and it is frequently curved. The anterior part of the
shell is evidently subject to much friction during the
process of excavation, and is invariably divested of the

PH0LADIDJ2. 93

epidermis : it does not show the slightest indication of
any corrosive action j and the inside is highly polished,
although in close contact with the mantle.

It is the Chama parva of Da Costa, Pholas pusilla of
Poli and Olivi (but not of Linne), P.faba of Pulteney,
My a Pholadia of Montagu, P. Mans of Brocchi (but not
of Chemnitz), G. modiolina of Lamarck, Mytilus amb'i-
guus of Dillwyn, G. pelagica of Risso, G. cuneiformis of
Philippi (but not of Lamarck), as well as his G. Polii
and G. Poliana, G.fulva of Leach, and G. tarentlna of
Costa.

Family XXIII. PHOLA'DIME, Gray.

Body conico-cylindrical : mantle thickened at its outer edges,
and reflected behind, where it covers the hinge of the shell :
tubes large, extensile ; orifices of both or of one of the tubes more
or less cirrous : gills, a pair on each side, narrow, for the most
part adherent on one of their sides, and prolonged into the
branchial tube : palps also two on each side, coarsely pectinated
as well as the gills : foot short and sucker-like, never bys-
siferous.

Shell wedge-shaped, convex, equivalve, inequilateral, widely
gaping in front (except in the adult Pholadidea and allied
genera, which have the gape closed by a shelly layer), and at
the posterior end in all the genera but Xylophaga : epidermis
membranous, thin : beaks not prominent : hinge connected by
the anterior adductor muscle, which supplies the place of a
ligament; it is covered by a thickened fold of the mantle,
which is to a greater or less extent protected externally by
one or more testaceous shields or plates ; the hinge is inar-
ticulated, but sometimes furnished with laminar or tubercular
processes : apophyses, as in Terebratula, falciform, springing
forwards from beneath the hinge, one in each valve : pallial
and muscular scars indistinct.

These burrow in stone, clay, mud, sand, wood, peat,
and other mineral and vegetable substances. In the
holes thus excavated thev dwell at ease, never of their

94 PHOLADIDiE.

own accord removing from one place to another, in this
respect unlike the Solen and other bivalves which make
only a temporary sojourn in sand or mud. The extensor
muscle, aided by the prickly surface of the shell, serves
to keep the Pholas fixed in its case when it rises to the
surface in search of food. The depth of the hole exca-
vated by P. Candida is between 5 and 6 inches ; its shell
and tubes, the latter being fully extended, measure only
4 inches. The ascent must be effected by stretching
out the foot ; and by contracting it the Pholas can
descend to the bottom and retreat for shelter. I have
observed the latter fact ; and I believe the above to be
the correct explanation of it. The Pholas gets rid of
the excavated material by closing the valves of its shell,
and forcibly expelling the detritus by a spasmodic action,
through the larger or incurrent tube, together with the
water contained in the body. The detritus is not re-
moved to any distance ; and some of the finer particles
are occasionally washed by the waves into the hole, and
line its sides. Mr. Osier and M. Cailliaud account in
other and different ways for this phenomenon. Accord-
ing to the latter naturalist, the maternal care of the
Pholas for its young is very peculiar. He says that,
like the Gastrochcena, it makes with its acidulated
siphons small oval holes in the surface of the calcareous
rock which it inhabits, and inserts in these holes a
portion of its brood ! This remarkable instinct has its
parallel in the case of Teredo, if we place equal confi-
dence in everything that Sellius wrote on that subject.
Most of the Pholadidce can entirely withdraw into their
shells : Pholas crispata is an exception among the
British kinds. If a layer of peat, mud, or shale in-
habited by Pholades is too thin to contain them, they
will either perish or their growth will become stunted.

PHOLADID.E. 95

They usually burrow in a slanting direction. When
several individuals occupy the same layer, one of them
seldom interferes with another by breaking into the
hole of its neighbour ; but it pursues a parallel course.
Cases, however, now and then occur in which no such
forbearance is shown. The avoidance of each other's
burrow is probably owing to the extreme sensitiveness
of the foot or perforating organ, which is always pushed
out in advance to feel its way. The structure of this
organ is similar to that of the foot in Teredo and
Patella, being thinner and of finer texture in the middle
than at the circumference ; it is nearly circular and
truncated. Dr. Fischer believes that the foot in Phola-
didea, when it has ceased to perforate, becomes atro-
phied. It is then hindered from further action by the
shelly wrapper which closes the front gape of the shell,
and is therefore useless. As far as has been hitherto
observed, all the members of this family possess the
hyaline ? style " or cuspidated process, which is found
in many of the other Conchifera. The use of this
curious internal apparatus is unknown. Some phy-
siologists consider it a digestive appendage of the
stomach ; but Cailliaud is of opinion that it is connected
with the fecundation of the eggs, in consequence of
these mollusks being hermaphrodite. Lacaze-Duthiers,
however, regards them as of distinct sexes. The splen-
did work of M. Emile-Blanchard, now in course of publi-
cation, and entitled " 1/ organisation du Regne Animal,"
ought to be consulted with respect to the internal
structure of the Pholadidce. He has shown that each
lobe of the mantle on the anterior side is extended, and
reflected behind, where they are united and form a long
and muscular expansion apart from the rest of the body.
Siebold thought that at the base of the siphonal tentacles

96 PHOLADID.E.

in Pholas there were eyes analogous to those with which
the scallop is furnished ; but Blanchard could not detect
any such organ, although he had traced all the nerves in
this part of the body to their extremities. Born's view,
that the hinge is connected by a ligament, was adopted by
Clark. It is incorrect. Pholas has no ligament, concho-
logically speaking ; and its proper function, that of open-
ing and closing the valves, is performed by the anterior
adductor muscle. The shells are white or colourless,
owing to their confined position. Their composition is ex-
ceedingly firm, and partakes of the nature of arragonite.
This is sometimes necessary, in order to sustain the
almost constant pressure of the shell against hard rocks.
Adanson seems to have mistaken the nature of the
dorsal shields (or " accessory valves," as they have been
also called) when he used the same word, " palettes," to
designate these appendages and the opercular bars of
Teredo. The falchion- shaped shelly processes which
issue from the hinge were first observed by Lister,
and called " apophyses." Klein afterwards applied the
same term to the dorsal shields. The true apophyses
were regarded by Deshayes as cardinal teeth. But it
seems to me that they have nothing to do with the
hinge, and that they are formed by a different part of
the mantle. They are probably of service in keeping
the viscera in their proper place, and protecting them
from the strain caused bv the muscular exertions of the

at

animal in the act of boring.

The notion that the shell is the instrument of perfo-
ration originated with Bonanni, in 1684. It was adopted
in the last century by Adanson, Born, and others ; and
in the present century most zoologists of note and expe-
rience have favourably entertained it. No one, however,
can be compared to M. Cailliaud of Nantes in respect

PHOLADID.E. 97

of the zeal, ability, and conscientious labour with which he
has investigated the subject; and he may be justly termed
the apostle of this theory. His researches have been
carried on, with scarcely any intermission, for more than
twenty years ; and although I have ventured to disagree
with him in the present instance, I still entertain a pro-
found respect for his opinion. Were I to become con-
verted, it would be solely by his arguments. The careful
and precise experiments made by him leave no doubt
that the shell can be used by man as an instrument of
perforation ; it by no means follows that it is so used
by the mollusk. It is easy to scrape with the edge of a
limpet-shell a cavity in chalk or shale, such as Patella oc-
cupies ; but can it be imagined that in this case the shell,
instead of the foot, is naturally employed for that pur-
pose? I believe that all the phenomena which have
been attributed by Cailliaud to the mechanical action of
the shell may be accounted for by the theory of Sellius,
or rather of his predecessor Reaumur. For instance,
the fine and regular strise, which are observable on the
sides of the cell of a Pholas, are unquestionably caused
by the friction of the spinous ridges that ornament the
shell. These strire are wanting at the bottom of the
cell, and are replaced there by a far more delicate elabo-
ration, which I am of opinion is produced by the sucker-
like motion of the foot. Assuming the latter to be the
instrument of perforation, the shell would partake of its
motion, and would rasp the walls of the cell while the
foot was doing the work of excavation. The prickly
surface of the shell, stretched to its full extent by the
adductor muscle, is pressed against the sides or walls of
the cell, and acts as a fulcrum. Born's idea, repeated
by Cailliaud, viz. that the foot acts as the fulcrum or point
of leverage, is exactly the reverse of mine. Besides, let

VOL. III. f

98 PH0LADID.E.

us not lose sight of the fact that the shells of many mol-
lusca which are not borers have also prickles or spines
like those which cover the shell of a Pholas. Anomia,
Pecten, Lima, Area, Cardium, Venus, and Psammohia
offer examples among the British shells of this sort of
ornamentation. Such asperities appear to result from
a superfluous secretion of shelly matter, which it is con-
venient to dispose of in this way ; they strengthen the
fabric of the shell, but are of no further service to its
constructor. To my desire of doing justice to the inves-
tigation of M. Cailliaud must be added an apology for
having, in the introduction to the first volume of this
work, misinterpreted his views as to the mode in which
the Pholades excavate rocks. The mistake was partici-
pated by Dr. Fischer, and arose from the following pas-
sage in M. Cailliaud' s ' Memoire sur les Mollusques
perforants' (1856) — "les siphons des pholades, coupes
en pieces et morceaux, attestent (dans les temps voulus)
la presence de cette liqueur acidulee. Elle est done
faible puisqu'elle ne parait sous aucun rapport nuire k
Forganisation de ces animaux, et cependant elle dissout
des test de coquilles tres-durs, les calcaires les plus com-
pacts." (p. 27.) I certainly understood by this, that
M. Cailliaud was of opinion that the Pholades employ
an acid or corrosive solvent in excavating calcareous
rocks ; but he has since distinctly asserted that they
make use of their shells only. It had been generally
supposed that Pholas does not secrete an acid. M.
Thorrent, however, in the i Journal de Conchyliologie '
for 1850, proved that an acid exists in P. crispata ;
and this important discovery has since been confirmed
by M. Cailliaud as to other species of Pholas. But how
do the fry perforate ? Are Ave to suppose, with M. Cail-
liaud, that the parent makes with its acidulated siphons

PHOLADID-E. 99

minute holes in the rock for the reception of its progeny?
It does not appear that he has ever witnessed so extra-
ordinary a proceeding ; and even if it is offered as a pro-
bable explanation of the method by which the fry effects
its entrance into the stone, this would only apply to the
case of chalk or limestone, which being calcareous can be
dissolved by an acid, and not to that of gneiss, sandstone,
peat, or wood, which are not liable to be thus acted upon,
and in which the Pholades more frequently take up their
abode. If the foot is to be considered merely as a point
d'appui, the motive power would be altogether wanting
while the young Pholas, encased in its tender shell,
remains outside the much harder material which it has
to penetrate. The same remark holds good with regard
to other mollusca which excavate stone and wood. I
am more than ever convinced that the modus operandi
is similar in all these cases, and that the laws of Nature
are more simple and uniform than those which direct
human actions ; nor do I infer from the case now before
us,

"That many things, having full reference
To one consent, may work contrariously."

When the Pholas has to make its habitation in clav
or sand, instead of in stone, no great amount of force
seems requisite. Reaumur in 1712 stated, from his own
observation, that P. Candida uses its lozenge-shaped and
comparatively large foot for this purpose. He took
several of them out of their holes, and placed them on
a clay as soft as mud ; each soon put out its foot, and
in a few hours made a fresh hole deep enough to contain
the Pholas, w r hich met with so little resistance and was
evidently anxious to conceal and shelter itself without
delay. Is it likely that the Pholas uses its foot or shell
according to the nature of the material w r hich it seeks

p2

100 PHOLADIDzE.

to inhabit ? Even where it has to erode the solid rock,
the quantity of water it takes in, and with which all its
tissues are saturated, cannot fail to render the process
more easy. On the importance of this latter agent Valen-
ciennes lays considerable stress in advocating the theory
that the rock is worn away by the continual friction of
the foot. The work of perforating gneiss, in which M.
Cailliaud discovered living Pholades, must be extremely
slow and gradual. It takes probably a year and a half
before a Pholas arrives at maturity ; by that time it has
made a hole 5 or 6 inches deep. One hundredth part of
an inch may therefore be reckoned its daily task. Time
is of course a necessary element in all operations ; and
it serves no less to advance the labours of the persevering
and patient shell-fish, than to scoop out valleys by the
agency of running waters and yielding glaciers,

" And waste huge stones with little water-drops."

The PholadidcB are distributed over the greater part
of the globe ; but the species, although prolific, are not
numerous. According to Searles Wood " Pholades have
been found fossil as early as the Lias"; and Chenu
says that they occur in the Jurassic, cretaceous, and
tertiary formations.

They comprise with the Teredinidce the multivalves
of Adanson and other writers of a later date ; but neither
the dorsal shields possessed by some species of Pholas,
as well as by Pholadidea and Xylophaga, nor the sheath
and pallets of Teredo are u valves " in a conchological
sense, any more than the opercula of many univalves.
Nor are any of these appendages homologous, or formed
by similar organs. Linne also considered Pholas a
multivalve, and placed it with Chiton and Lepas. Pul-
teney was not so far from the mark when he conjectured

PHOLAS. 101

that the Tmiicata were shell-less Pholades. Schumacher
ranged Pholas with the pedunculated Cirripeds, and
Teredo in another division of his medley collection
of Monothalami. In BlancharcVs system the present
family is regarded as closely allied to the Myida?. The
number and position of the dorsal shields are useful
characters to distinguish sections of genera, but they do
not appear to be of any greater value. Ever since the
groups called families were instituted in classifying the
animal kingdom, conchologists have been busy in framing
svnonvms for the one of which we now treat. These
synonyms, with the exception of two (Adesmacea, De
Blainville, and Cladopoda, Gray), were compounded out
of the generic name Pholas ; and the ingenuity of the
svstematists mav well excite our admiration, or some
other feeling of perhaps not a laudatory kind, when we
find no less than fourteen of such compositions.

Genus I. PHOLAS*, Lister. PI. IV. f. 1.

Body oblong or oval, usually incapable of being altogether
contained within the shell : tubes united except at their ex-
tremities, and enveloped in a membranous retractile sheath,
as in Mya ; both orifices cirrous : gills nearly equal : palps
large and broad : foot truncated, but expansible to a certain
extent.

Shell shaped like the body, nearly opaque and lustreless,
more or less covered with rows of prickles : beaks concealed
by a fold of the hinge-plate in each valve : apophyses long and
partly concealed within the hinge : pallia! scar narrow and
deeply sinuated : muscular scars w r idely separated ; anterior
elongated, posterior short : dorsal shields usually present, and
varying in number, size, and position ; when absent, their
place is supplied by a tough integument of the mantle.

The present genus is not so ancient as has been gene-

* Lurking in dens.

102 PHOLADID^.

rally supposed. The cpcoXU of Aristotle was a kind of
fish, which he classes with the mullet ; and the (£&>\a?
of other Greek writers appears to have been Litliophaga
dactylus, which is certainly the Pholas of Rondeletius
and Aldrovandus. Our species of Pholas are the " Pid-
docks " of old English naturalists, and the " Pitaux '* or
" Dails " of the French. Mr. W. Wood remarks that
on the coast of Normandy they are eaten in abundance,
well seasoned and cooked with bread-crumbs and fine
herbs. They are also reckoned a delicacy when pickled
in vinegar. In the neighbourhood of Dieppe a great
many women and children, each provided with an iron
pick, are employed in collecting them, either to sell in
the market, or for fishermen's bait. They are almost
entirely littoral,

" Entomb' d upon the very hem o' the sea."

The property which they possess of shining in the dark
is very remarkable. It was mentioned by Reaumur in
the Mem. de l'Acad. Roy. for 1723; and his communi-
cation, "Des Merveilles des Dails, ou de la lumiere
qu'ils repandent," shows his power of accurate observa-
tion. He says that this property is not confined to the
skin or outer membrane of the Pholas, but that every
part of the body is imbued with it, and when the Pholas
is cut into pieces, each portion is luminous. Much of
the water that drops from them sparkles brilliantly.
The phenomenon is visible only when the Pholas is in a
moist state. He dried several specimens, and after four or
five days moistened some with common or fresh water,
and others with water in which sea-salt had been dis-
solved. In every case the phosphoric light reappeared,
but with less intensity than at first. When the Pholas
was put into brandy, the luminosity almost instantly
disappeared. No light is emitted by them in a dead or

PHOLAS.

103

putrid state. He attributed the phenomenon (which he
considered a ' ' vrai phosphorus naturel ") to a fermen-
tation, resulting from the breeding-season ; and he
supposed that it was analogous to the cases of the male
glowworm and centipede. These experiments were
made in autumn, and at other times of the year when
the weather was not very warm. Dr. J. M. Davis
examined P. dactylus at Tenby in the autumn of 1840 ;
but although he kept it alive and in a vigorous state for
many weeks, it never was luminous or phosphorescent.
Out of fifteen living individuals of this species obtained
by M. Cailliaud at the end of April and in December
1854, ten or tw r elve shone in the dark. In none of these
did the foot exhibit any light; only the mantle and
siphons, which when rubbed with the finger were ex-
tremely phosphorescent, and shone even through the
shells. The siphons were furnished with it in such
quantity, that he w r as able to trace with them bright
marks on a table. He endeavoured, but in vain, to find
the same property in other perforating mollusks. I
am disposed to believe that this luminosity is caused
not by the Pholas, but by extraneous microscopic
organisms. The subject ought to be further investi-
gated. M. Necker has show r n that the shell of Pholas,
as well as of several other mollusca, is formed of arra-
gonite ; and inasmuch as that mineral slightly exceeds
calc spar in specific gravity (the proportion being 2 - 9 to
2'7 or 2*8), he came to the conclusion that Pholas
excavates calcareous rocks by means of the prickles
with which the shell is furnished, aided by an acid.
But he placed Helix nemoralis and Mytilus edulis in the
same mineralogical category with Pholas, and ascribed
a still greater density to the common oyster. It is also
important to notice that the impurity of most calcareous

104 pholadidjE.

rocks increases their hardness, and that the admixture
of organic matter with the mineral ingredient in the
shell diminishes the specific gravity of the latter.

The animal is partly the Hypogcea of Poli. Three or
four genera have been proposed by Leach and Gray for
the shells of certain species. Pholas, being derived from
the Greek, is feminine.

A. Shell oblong : hinge-plate furnished behind with a layer
of cells : dorsal shields 4, viz. 2 anterior, placed side by
side ; 1 cardinal, and complicated ; 1 posterior, and
elongated. Dactylina, Gray.

1. Pholas dac'tylus"*, Linne.

P. dactylus, Linn. S. N. p. 1110; F. & H. i. p. 108, pi. iii.

Body oblong, whitish, sometimes tinged with blue or yellow :
tubes more or less covered with short papillae ; orifice of longer
tube margined with about a dozen fringed tentacles, besides as
many intermediate smaller ones which are ciliated on the
sides ; the excurrent tube has its orifice either j>lain or mar-
gined with a few short cirri ; the points of the siphonal ten-
tacles or cirri are brownish ; outer sheath brown or of a
pepper-and-salt colour : foot rather obliquely fixed to the rest
of the body by a long, cylindrical, thick, fleshy, white stalk.

Shell elongated, somewhat obliquely twisted on the anterior
side, moderately solid : sculpture, 40-50 longitudinal rows of
small prickles or vaulted scales, which are formed by the in-
tersection of slight longitudinal ribs and wavy transverse
striae ; these prickles extend over the greater part of the shell,
but they are much stronger and more crowded on the anterior
side, and less so in front, and, especially, towards the posterior
side, where they are altogether Wanting ; this latter part is
often coarsely and irregularly granular, as if from an imperfect
consolidation of the shell; the whole surface also is closely
puckered: colour whitish: epidermis pale yellowish -brown,
more persistent at the edges : margins narrow, angular, and
more or less attenuated or beaked at the anterior end, widelv

* Shaped like a finger; formerly, but erroneously, supposed to be the
S&ktvXos or dactylus of the ancients.

PHOLAS. 105

open and exhibiting an oval gape towards the front, whence
there is a regular slope both above and below to form the
posterior end, which is rounded, and has a sharp edge, with a
decided gape ; dorsal margin on the anterior side short and
obliquely convex: beaks very near the anterior end: hinge-
line flexuous : hinge-plate extremely broad ; it forms a double
fold, one of which has a free cutting edge and projects out-
side in the middle of the hinge-plate, and the other adheres
for the most part to the anterior side, its outer edge being
likewise free ; the interspace between these folds is fitted with
about a dozen transverse plates, besides occasionally a few
short intermediate processes in the opposite direction ; the
hinge-plate is sometimes crossed in its thickest part by two or
three oblique tooth-like ridges : apophyses strong, broad, and
curved, concave and expanding outwards : dorsal shields, two
on the anterior side, large, irregularly lance-shaped, broader
in the line of the beaks, and often cracked in a direction
radiating from outside ; another in the middle is morticed into
the two anterior shields, and is of an irregularly triangular
shape, twisted, and very solid, lying perpendicularly across the
valves; the fourth or posterior shield is long, narrow, and
slightly bent, so as to fit the slope of the shell on that side.
L. 1-75. B. 5.

Yar. 1. gracilis. Shell smaller, more slender, and of a
finer and thinner texture.

Yar. 2. decurtata. Shell stunted or truncated at the pos-
terior end, and of a coarser and more solid texture ; sculpture
closer and usually effaced.

Habitat : Slate rocks, coal-shale, new-red sandstone,
chalk, marl, peat, and submarine wood in Guernsey,
the south of England, and Bristol Channel ; Seacombe,
Lancashire (Dr. Walker) ; north, east, and south of
Ireland. Var. 1. At extremely low tides below the
Warren, Exmouth, in pure sand (Clark). Var. 2. Oc-
casionally met with in hard rocks. Fossil at Belfast
(Grainger) ; Sussex (Godwin- Austen) ; in the Scotch
glacial beds at Ayr and Stevenston (J. Smith and
Landsborough) ; Tarento (Philippi) : and the variety

F O

106 pholadiDjE.

gracilis was found by M. Cailliaud on tlie faluns of
Touraine. Its exotic range in a recent state extends
from Norway to Sicily and Algeria. M f Andrew describes
his Spanish specimens as being of small size. Cailliaud
has noticed it as perforating micaceous schist at Croisic
in Lower Brittany.

The " Pierce- Stone " of Petiver. In Da Costa's time
it was reckoned "a very excellent and dainty food."
Philippi says that it is esteemed in Sicily by all classes ;
and at Rocheile it is sold in the market and served at
the best tables. I am not aware,, however, that it is now
eaten in Great Britain ; although it is often dragged out
of its hole by our fishermen to entice and capture their
finny prey. It buries itself eight, ten, or even twelve
inches ; and its tubes, when fully extended, are three
times the breadth of the shell. Like all its congeners
this species is very prolific. In a spot three feet
square at Saundersfoot near Tenby, Mr. Jordan dug up
100 living specimens. He calculated, that owing to the
removal by the waves of a foot in depth of mud during
the autumn equinox of 1863, no less than 15,000 in-
dividuals perished ; their empty shells remained below
the surface. Some of them might also have been choked
and destroyed by a silting up, as well as by the mud
being disturbed in the course of its removal. The
late Dr. Lukis took a P. dactylus out of peat, and kept
it alive in clear sea water for four or five days. At the
end of that time it died. The shell had become so thin
from excessive absorption of its calcareous substance,
that he was unable to lift it with the animal out of the
water in a perfect state. Another intelligent and inde-
fatigable naturalist, Mr. Peach, endeavoured to discover
the way in which this Pholas makes its cell. He
carefully and patiently watched 15 or 16 of them in a

PHOLAS. 107

slab of clay-slate, and placed marks iu order to see if
they had any rotatory motion ; but he fonnd that they
all invariably retained the same lateral position, and
that the movement was vertical onlv. When the shell
has been abraded or worn by rubbing against the sides
of its stone cell, the new layers formed in front have of
course their prickles, when they exist, quite perfect and
sharp. Specimens now and then occur which measure
about 6 inches in breadth.

The synonyms are antiquated ; and two only are post-
Linnean, viz. P. muricatus of Da Costa, and P. Mans
of Pulteney. The animal is the Hypogcea verrucosa of
Poli.

B. Shell oblong : dorsal shield single, posterior, and elongated.

Bar tiea, Leach.

2. P. can'dida*, Linne.

P. candidus, Linn. S. N. p. 1111. P. Candida, F. & H. i. p. 117, pi. iv.
f. 1, 2.

Body oblong, dirty white with a faint tinge of brown : tubes
more narrow, slender, and elongated than in P. dactylus ;
larger tube funnel-shaped, grooved inside lengthwise like
the barrel of a rifle, and appearing as if marked with white
or light-brown stripes ; its orifice is surrounded by about a
dozen papillae which terminate the grooves ; smaller tube
cylindrical, and contracted or bell-shaped at the top, with its
orifice either plain or surrounded by a few papillae ; sheath
minutely tuberculated : foot small, oval, attached by a com-
pressed stalk.

Shell elongated, tumid, and thin: sculpture, 25-30 longi-
tudinal rows of sharp thorn-like prickles, which cover all the
surface except at each end, and radiate from the hinge out-
wards ; on the anterior side the prickles are stronger but not
crowded : colour chalky- white : epidermis light-brown, some-
what fibrous on the posterior side, and forming delicate thread-
like lines to connect the rows of prickles : margins rounded

* White.

108 PHOLADID.E.

or slightly angular at the anterior end, exhibiting a long and
rather narrow gape towards the front, whence there is a re-
gular slope (less above than below) to the posterior end,
which is rounded and has a sharp edge, with a moderate gape ;
dorsal margin on the anterior side short, concave, and smooth:
beetles very near the anterior end: hinge-line nexuous: hinge-
plate extremely broad, and forming a single fold on the um-
bonal area, to which it adheres, the outer edge being free ;
the centre is marked across by a few indistinct furrows, re-
sembling the walls of the cells in P. dactylus, as sometimes
seen in that part of the shell ; and it is furnished with a
sharp ridge, that winds obliquely from above the apophysis
to the posterior side, and ends in a projecting spur-like pro-
cess ; this is more prominent in the right than left valve :
apophyses strong, narrow, curved, and concave at the point :
dorsal shield slightly bent, and shaped like a lance-head with
the point outwards ; it has a small boss near the broader end,
from which a shallow groove runs in the middle to the other
end, with a slope on each side ; the lines of growth are dis-
tant, diagonally arranged, and numerous. L. 1. B. 2-75.

Var. subovata. Shell smaller, and somewhat oval, in con-
sequence of the posterior end being shortened or less de-
veloped.

Habitat : Coal-shale, Great Oolite, and Oxford
clay, chalk, marl, peat, submarine wood, and sand, from
Guernsey to Oban and the Moray Frith, as well as
throughout Ireland. Fossil at Belfast (Grainger, who
has recorded a specimen from that deposit measuring
3 inches by 1^) j Bracklesham (Dixon) ; Christiania
district in the newer beds, 100-120 feet above the
present level of the sea, and at Drontheim, 30—10 feet
(Sars). Abroad, it ranges from Iceland (Olafsen and
Povelsen, t /7V/e Miiller) and Norway (Loven) to the Black
Sea (Nordmann, fide, Middendorff) ; Sicily (Philippi) ;
and Algeria (Deshayes and others).

Mr. Clark found it living in sand at Exmouth, and
M. Cailliaud in gneiss at Croisic. It occurs in com-
pany with P. dactylus and P.parva at Guernsey. This

FHOLAS. 109

species differs from P. dactylus in its more convex
shape and thinner texture ; the front gape being much
narrower ; not having any dorsal cells, nor more than
a single shield; and in possessing a strong and remark-
able fold on the hinge-plate.

The specific name was given by Lister. Spengler
described aud figured the present species as the P.
papyraceus of Solander ; but his description, quoted by
Spengler, is more like that of a young P. crispata. It
is also the P, dacty hides of Delle Chiaje, and Barnea
spinosa of Risso. The P. cylindrica of J. Sowerby,
from the Red and Coralline Crag, appears to be inter-
mediate between the present species and the next.

3. P. parva*, Pennant.

P. parvus, Penn. Brit. Zool. iv. p. 77, pi. xL f. 13? P. parva, F. & H.
i. p. Ill, pi. iv. f. 1,2, pi. ii. f. 2, and (animal) pi. F. f. 3 & 3 A.

Body oval, milk-white : mantle invested at its edges by a
thin membrane : tubes marked inside lengthwise with alternate
brown and white stripes ; orifices scalloped, but neither are
cirrous ; sheath thick, reddish-brown, covered with nume-
rous granular papillae ; these become larger towards the ex-
tremity of the sheath, which is encircled by a fine pile or
fringe : foot oval when at rest, rounded in front and pointed
behind when protruded, and attached by a long cylindrical
fleshy stalk.

Shell oblong, somewhat compressed, rather solid : sculpture,
very numerous transverse rows of imbricated and flexuous
ridges, which are puckered or flounce-like on the crests formed
by the intersection of slight and less numerous longitudinal
ribs ; these markings are more crowded on the anterior side,
and in the adult gradually disappear towards the posterior
side, which is smooth or only exhibits some irregular lines
of growth ; there are seldom prominent and sharp prickles as
in the preceding two species : colour white, sometimes slightly
stained with brick-red from the matrix in which the shell is
imbedded : epidermis light-yellowish and irregularly fibrous,

* Small.

110 PHOLADID.E.

more persistent on the posterior side : margins acutely an-
gular or beaked at the anterior end, with a wide oval gape
towards the front, whence there is a regular slope above and
below to the posterior end, which is broad and rounded, with
sharp edges and a moderate gape ; dorsal margin longer than
in P. Candida, concave and sculptured like the rest of that
side : beaks placed at a distance of about |-ths from the
anterior end : hinge-line flexuous : hinge-plate extremely
broad, folded over the umbonal area but not adhering to any
part of it; the centre is marked as in the last species, and
furnished with a thick knob or tubercle, which apparently
serves by its intervention to prevent the valves from being
squeezed too closely together; the crown of this tubercle is
consequently more or less worn by continual pressure, and it
is connected with the dorsal posterior margin by a sharp ridge,
so as to give it additional strength : apophyses of moderate
breadth, not much curved, and nearly flat : dorsal shield some-
what curved, and lanceolate with the point outwards ; it has a
small boss close to the broader end, which is bent inward ;
there is a slight depression down the middle, and the lines of
growth are distinct, diagonally arranged, and numerous : in-
side polished and occasionally iridescent, usually showing the
external sculpture, and having the edges notched on the an-
terior side. L. 0*8. B. 1*85.

Var. quadrangida. Shell smaller and more contracted
at each end, with closer and finer sculpture.

Monstr. tubercidata. Shell divided into two nearly equal
parts by a longitudinal irregular furrow. P. tuberculata, Turt.
Conch. Dith. p. 5, t. 1. f. 7, 8.

Habitat : New-red sandstone, marl, clay, and sub-
marine peat, at Guernsey and on the southern coasts of
England; Oxwich Bay near Swansea (J. G. J.) ; Aber-
gelly, Denbighshire (Pennant) ; Dublin Bay (Warren) ;
near Belfast (Hyndman) ; St. Cyrus, Kincardineshire
(Brown). The North Welsh and Scotch localities are
doubtful ; because Pennant's shell was probably the
young of P. crispata, and the single specimen said to
have been found at St. Cyrus may have been from
ballast. The variety is from indurated clay, and the

PHOLAS. Ill

monstrosity from the same material as well as from
sandstone. The furrow or groove in the latter case is
quite accidental, and does not even extend to the beaks.
It was probably caused by an injury or obstruction of
the mantle in front. I have already noticed similar
cases in other conchiferous mollusks ; and the uni-
valves are also subject to this kind of partial deformity.
P. parva has been observed by De Gerville and many
other conchologists in the north of France, by M f Andrew
at Malaga (of small size), and by Weinkauff at Algiers.

On a fine living specimen, which I took out of its
burrow in sandstone at Exmouth, was a Truncatulina,
full of sarcode. It still adheres to the crest of
one of the ridges on the most exposed part of the
anterior side of the Pholas. Is it possible that this
part of the shell could have been employed in grinding
the stone, and that the delicate Foraminifer remained
uncrushed ? In the instance just mentioned the pos-
terior side of the Pholas was more worn than the
other. Sometimes the entire sculpture of the shell is
quite perfect, and appears not to have suffered the
slightest attrition. The oval shape, smaller size, close
and delicate sculpture, wide gape in front, large tubercle
on the hinge-plate, and more central position of the
hinge will readily serve to distinguish P. parva from P.
Candida. My largest specimen is 2 \ inches in breadth.

Da Costa, Boys, and Donovan mistook the young of
P. crispata for the present species ; and it is not un-
likely that they were misled by Pennant, judging from
his ambiguous description and figure. The last-named
author confounded his species with Martesia striata.
Our shell may have been known to Lister, who says,
with reference to P. crispata, that sometimes it has a
third small shell at the hinge. Solander called it P.

112 PHOLADID.E.

crenulatus. Perhaps it is the P. callosa of Lamarck
from the neighbourhood of Bayonne. His diagnosis,
and especially the words " valvarum callo cardinali pro-
minnlo globoso/'' are more applicable to P. parva than
to P. dactylus. It certainly is his P. dactyloides. Al-
though the very specimens which he thus described
were received by him from Dr. Leach as the P. parva
of Montagu, he capriciously rejected that name, and
substituted an inappropriate one of his own. It is
the P. ligamentina of one of the earlier works of
Deshayes, and Anchomasa Pennantiana of Leach.

C. Shell oval; valves furrowed lengthwise: dorsal shield single,
placed centrally, extremely small and triangular. Zir-
phcea, Leach.

4. P. crispa'ta"*, Linne.

P. crispata, Linn. S. N. p. 1111 ; F. & H. i. p. 114, pi. iv. f. 3-5.

Body very thick, reddish-brown : tubes long, encircled with
branched papillae : sheath velvety : palps much smaller than in
the other species : foot oval.

Shell convex with a slight depression in the middle, solid,
and of a coarse and rugged aspect ; it is divided into two
nearly equal parts by a rather broad furrow, which runs
obliquely from the beak in each valve to the front margin :
sculpture, about 20 longitudinal rows of imbricated prickles,
formed by the intersection of the ribs with numerous trans-
verse scalloped ridges ; these markings are on the anterior
side only, and do not extend to the separating furrow ; the
rest of the surface is nearly smooth, or exhibits the usual
irregular lines of growth: colour dull white with a slight
tint of yellow : epidermis whitish, becoming brown towards
the edges, wrinkled obliquely, and leaving its impress on the
surface of the shell : margins acutely angular or beaked at
the anterior end, with a very wide heart-shaped gape towards

* Curled.

PHOLAS. 113

the front, where there is an upward curve to the posterior end,
which is broad and rounded, with sharp edges and a large
gape ; dorsal margins sloping almost equally on each side, the
posterior being the larger of the two : beaks placed at a dis-
tance of about fths from the anterior end : hinge-line flexuous :
hinge-plate extremely broad, folded over the umbonal area,
and adhering to the greater part of it ; it has no protuberance
or other process, and is consequently more or less worn away
in the centre by continual contact : apophyses curved, some-
what dilated, and concave at the points : dorsal shield trian-
gular, with the apex downwards and the sides turned in ; it
is almost rudimentary, and covers only the angle formed by
the meeting of the hinge-plate in each valve on the posterior
side ; the lines of growth are strong : inside marked with a
ridge, which corresponds to the outside furrow, and termi-
nates in a blunt tubercle : pallial scar narrow, very deeply
sinuated, and extending far within the shell : muscular scars
conspicuous ; posterior pear-shaped, lying near the edge of
the dorsal slope. L. 1*6. B. 2*8.

Habitat : Mica-schist, coal-shale, Great Oolite, Ox-
ford clay, gypsum, and peat, on various parts of the
coast from Unst in Shetland (Edmondston and Dawson)
to Weymouth (Metcalfe), and throughout the greater
part of Ireland. Da Costa gives Cornwall also as a
locality. It is found in all our upper tertiaries from
the Belfast bed to the Coralline Crag, and especially in
boulder-clay and other deposits of the glacial period.
Uddevalla (Malm) ; Christiania, in newer deposits,
100 feet above the sea-level (Sars) ; Monteleone in
Calabria, as P. vibonensis (Philippi). Its extra- British
range in a recent state is chiefly northern. Iceland
(Mohr and Spengler); Scandinavia (Muller and others);
Heligoland (Frey and Leuckart) ; coasts of Holland
(Waardenburgh) ; north of France (De Gerville and
others) ; Charente-Inferieure (Aucapitaine) ; Marseilles
(Matheron, fide Philbert); it is also extensively distri-
buted in the New "World, e. g. Canada and the United

114 PHOLADIDiE.

States (Bell, Gould, and others); N.W. America, Van-
converts Island, and California (P. Carpenter) .

Captain Bedford informs me that it is eaten by the
poor at Oban. Inside the mantle of several specimens
Sars found a large parasite, about an inch long, which
he believed to be the Malacobdella grossa of Miiller.
The shells imbedded in stone are often stunted and
much rubbed ; but some which Bouchard-Chantereaux
took from the trunk of a tree entangled in a fisherman's
net at sea, and others noticed by Mr. Wright from turf
at low-water mark, were in a remarkably fine state of
preservation, as well as more convex. They seldom
exceed on our coasts 3 inches in breadth. Mighels,
however, mentions a specimen brought up on the fluke
of an anchor in Portland Harbour, U. S., that was
4^ inches ; and Grainger found valves in the Belfast
deposit of the same size.

Lister suspected that it might have been the Peloris
of the ancients. Was not that the Lithophaga dactylus
of modern naturalists ? Petiver gave our shell the name
of " Furrow-riVd Pholade-Muscle," and Da Costa
that of Pholas bifrons ; Gmelin called it Solen crispus.
In the tenth edition of the ' Systema Naturse ' it was
placed in the genus My a.

The hulls of ships returning from South America, off
which the copper has been accidentally stripped, and
pieces of mahogany drifted to these shores by the Gulf
Stream are occasionally drilled by Martesia striata.
This is more nearlv allied to Pholadidea than to Pholas,
and rej oices in the following synonyms : Pholas lignorum,
Eumphius, P. conoides, Parsons, P. nanus, Solander
(fide Pulteney) , and P. clavata, Lamarck, besides P. pu-
silla, Linne, which is the young state.

The P. sulcata of Brown, from Dunbar, appears to

PHOLADIDEA. 115

be an exotic species of Parapholas, perhaps the ovoideus
of Gould. That genus is distinguished by having two
furrows.

Genus II. PHOLADI'DEA*, Goodall. PI. IV. f. 2.

Body oblong, rather thin, capable of being contained within
the shell : tubes united throughout and terminating in a disk,
enveloped in a fine membranous retractile sheath ; the orifice
of the larger tube is cirrous, that of the smaller one plain :
gills very unequal : palps long and narrow : foot, in the young
and half-grown state very large, truncated, and sprioging
from a long stalk in the centre of the body ; in the full-grown
state it becomes atrophied, and is reduced to a mere point.

Shell oval, semitransparent but lustreless ; anterior part
covered with prickly ridges ; in the adult the front gape is
closed by a shelly dome or convex plate, and the posterior end
is furnished with a cup-shaped appendage, which has a texture
between shell and membrane : beaks much inflected, and con-
cealed (but not covered) by a fold of the hinge-plate : teeth
conspicuous, triangular : apophyses long, and partly concealed
within the hinge: dorsal shields two, formed in the adult only;
they are very small and triangular, placed close to the hinge on
the anterior side, and in a line with the fold of the hinge-plate.

The distinctive characters of this genus are rather
physiological and conchological than malacological ;
they are not developed until the Pholadidea has attained
its full growth. In the young and immature state it
does not differ from Pholas. The same peculiarity is
found in Martesia, Jouannetia, and other allied genera.
Mr. Berkeley has suggested to me that the cup-shaped
appendage may be the homologue of the pallets in
Teredo. It certainly occupies the same place in the
animal ; and both serve to protect the entrance of the
hole, although less efficaciously in Pholadidea than in

* Having the shape of a Pholas.

116 PHOLADID.E.

Teredo. This hypothesis seems preferable, in a bio-
logical point of view, to that of Deshayes, who likened
the appendage in question to the sheath of Teredo.
Very few species of Pholadidea are known ; and only
the typical species (P. papyracea) is fossil.

Pholadidea papyra'cea*, Turton.

Pholas papyracea, Turt. Conch. Dith. p. 2, t. i. f. 1-4. Pholadidea pa-
pyracea, F. & H. i. p. 123, pi. v. f. 3-6, pi. ii. f. 1, and (animal) pi. F.
f.4.

Body somewhat conical, bluish-white, mottled in the centre
with white roundish spots : tubes, when fully extended, often
twice as long as the shell is broad, at other times more or less
strongly wrinkled across ; orifice of larger tube encircled by
about 20 white cirri of different lengths ; sheath of a pale
reddish-brown hue, terminated by a fringe of short white
cirri : foot clear white or almost transparent : liver green.

Shell convex, thin, and of a delicate texture, depressed in
the middle, and divided into two nearly equal parts by a rather
narrow groove or constriction, which runs obliquely from the
beak in each valve to the front margin : sculpture, numerous
transverse scalloped ridges on the upper half of the anterior
side of the groove, the lower half being nearly smooth, much
thinner, and forming an oval-shaped dome ; the crests of the
ridges are sometimes prickly but not much raised ; the pos-
terior half is marked only by irregular lines of growth : colour
dirty white : epidermis very thin, partly fibrous at the pos-
terior end, light yellowish-brown : margins rounded (in the
young obtusely angular) on the anterior side, straight (in the
young widely gaping) in front, squarish (in the young rounded)
at the posterior end ; anterior dorsal margin upturned, doubled,
and folded back ; posterior one pinched up and nearly straight
(in the young sloping, so as to give a wedge-like appearance
to that part of the shell) : beaks placed at a distance of about
-|ths from the anterior end : hinge-line flexuous : hinge-
plate extremely broad, folded over the anterior side, and form-
ing a free angular projection above that part of the hinge ;
from the posterior part of the hinge issues an oblique triangu-

* Paper-like.

PHOLADIDEA. 117

lar plate in each valve (somewhat longer in the right), which
interlock and seem analogous to cardinal teeth in other bivalves :
apophyses curved, frequently twisted, narrow, and rather short :
dorsal shields often united, so as to form a single plate only,
which in that state is not unlike the shield in Pholas erispata ;
it is also deeply scored by the lines of growth : inside porcel-
lanous and glossy, showing on the anterior side the impres-
sions of the outside sculpture, and marked with a strong ridge,
which corresponds to the outside groove and terminates in a
blunt tubercle : scars as in Pholas crispata : the calj/cifortn
appendageis capacious, expanding considerably outwards, with
the edges slightly reflected ; it is divisible into two parts, one
belonging to each valve. L. 0-75. B. 1-5.

Var. aborta. Shell stunted and sometimes distorted, vary-
ing in size from 4-th to -Jths of an inch, exclusive of the
terminal process.

Habitat : New red sandstone or trias, at low-water
mark on the South Devon coast (Turton and others) ;
Hayle (Miss Hockin) ; peat, at Ballycotton, co. Cork
(Wright) ; submarine forest, Clonea near Dungarvan
(Farran) ; Dublin Bay ? (Thompson) ; sandstone at low
water, Castle Chichester near Belfast (Hyndman). The
variety has been taken from lumps of hard clay dredged
in deep water off Exmouth (Clark) ; in a piece of reddish
sandstone from deep water on the Cornish coast, drawn
up by a fisherman's line (Couch) ; in soft sandstone
dredged in 80 f. off the coast of Antrim (J. G. J.) ; in
indurated clay from 25 f. near Lismore in the west of
Scotland, with Nucula sulcata (Bedford) . Mr. Searles
Wood detected some shelly fragments which he referred
to P. papyracea in the Coralline Crag at Sutton ; other-
wise it appears to be unknown as a fossil. No foreign
locality has been recorded.

The burrows are occasionally flexuous. One of these
in sandstone has near its opening a piece of silex much
larger than the rest, which the animal appears to have

118 PHOLADID.E.

been unable to remove, and the passage is partially ob-
structed by it. The immature shell (which Turton
described and figured as Pholas lamellata) is not unlike
the young of Pholas crispata ; but it is more expanded
breadthwise, and the sculpture is much finer. This form
can always be traced in the earlier lines of growth of
every adult specimen.

The Pholas papyraceus of Solander is only known to
us by Spengler's quotation ; it probably was the young
of P. crispata. Turton, in his ' Conchological Diction-
ary/ first indicated the present species, and stated that
Dr. Goodall had given it the name of Pholadidea Los-
combiana ; but in his ' Conchylia Dithyra ' he retained
it in Pholas, and altered the specific name to papyracea,
on the authority of the sale catalogue of the Portland
Museum. In this catalogue occurs " Pholas pypyraceus
S/ J without any further particulars. I think the name
proposed by Dr. Goodall ought therefore to stand ; but
I hesitate to restore it, because the other name, papy-
racea, is generally recognized. Blainville called the
present species Pholadidea Goodallii; and in Griffith
and Pidgeon's edition of Cuvier's ' Regne Animal 9 it
bears the fearful name of Pholadidoides Anglicanus,
which, however, is matched by one in Leach's ' Mollusca
of Great Britain/ viz. Cadmusia Solanderia.

Genus III. XYLO'PHAGA*, Turton. PL IV. f. 3.

Body globular, all but the tubes, which, according to Dr.
Landsborough, are not included within the shell : mantle
puckered around the sides of the foot : tubes slender, covered
by a single sheath, very extensile, marked lengthwise with

* Wood -eating.

XYLOPHAGA. 119

crested ridges, which are pectinated at the edges, and separate
at the extremities : foot large, pillar- shaped, capable of being
protruded to some length.

Shell globular, semitransparent, and somewhat glossy,
divided lengthwise by a double ridge and furrow, which latter
is terminated inside by a small knob or tubercle in the middle
of the front edge ; anterior part triangular and sculptured by
numerous fine transverse striae ; middle area or strip narrow
and covered with oblique, finer and more crowded stria? ;
posterior part on the other side of the ridge nearly smooth,
and having the end closed : beetles as in the last genus : apo-
physes short and prominent : dorsal shields two, similar to
those in Pholadidea, but proportionally much larger and more
conspicuous as well as more complicated in structure.

Although Xylophaga resembles Teredo in the shape
and sculpture of its valves, and forms a connecting link
between the Pholadida? and Teredinidce, it is more
nearly related to the former than to the latter family.
Its habits are those of Pholas, in never perforating wood
or vegetable matter (its only habitat) to a much greater
depth than is necessary for the reception of its shell.
It has no testaceous sheath or pallets like Teredo ; but,
instead of these processes, its shell is provided with
dorsal shields or plates, similar to those possessed by
other members of its own family. In fact it is a short
Pholas, and not a long Teredo. More information as
to the animal is desirable : I believe it can be entirely
contained in the shell. The epidermis is conspicuous,
and closely invests the anterior side of the shell ; this
affords an additional proof that the valves in the present
case cannot be the instrument of excavation, otherwise
the epidermis would be the first thing to be removed,
from the continual friction to which that part must be
subjected. Only two species have been described, one
inhabiting the North Atlantic, and the other South
America ; both are recent.

120 PHOLADID.^.

Xylophaga dorsa'lis^ Turton.

Teredo dorsalis, Turt. Conch. Diet. p. 185. X. dorsalis, F. & H. i. p. 90.
pi. ii. f. 3, 4.

Body white, with the exception of the foot, which is tinged
with buff at its extremity.

Shell helmet-shaped, convex, thin, parted in the middle
(but not equally, owing to the wide anterior gape) by a broad
longitudinal groove, which is margined on each side by a sharp
narrow ridge : sculpture as described in the generic characters ;
the striae which cover the anterior and middle areas, as well
as their interspaces, are exquisitely crenulated or crossed
obliquely by still more numerous and microscopical striae
(giving the edges of the main striae an exquisitely beaded ap-
pearance) ; these main striae become more crowded or close-set
as the growth of the shell increases, being at first comparatively
few and remote ; there is a distinct line of demarcation between
the two sets of main striae ; the marks of growth on the pos-
terior area are concentric and tolerably regular : colour white :
epidermis yellowish-brown, more persistent on the anterior
side of the separating groove : margins obtusely angular on
the upper part of the anterior side, with a large triangular
excision on the lower part, so that when the valves are united
the opening is broadly heart-shaped ; they are curved in front
with a notch for the groove, and rounded at the posterior end ;
dorsal margins sloping abruptly and equally on each side : beaks
much incurved, somewhat nearer to the anterior end : hinge-
line projecting and pointed in the middle, by reason of the
abrupt inflexion of the beaks, with a deep curve on either side :
hinge-plate very broad on the anterior side, over which it is
folded, adhering to the umbonal area but free towards the
extremity, where the edges are turned up ; it is narrow in the
middle and on the posterior side : apophyses curved and pro-
jecting outwards ; that of the right valve is larger than the
other ; in aged individuals they are thick and tusk-like :
dorsal shields not unlike the opercula of Neritina Jluviatilis,
but having a less decided spire and doubled underneath at
the wider end ; they lie close to the beaks, on the outside of
the dorsal anterior margin : inside glossy, marked with a broad
and strong rib, which corresponds to the external groove, and
sometimes also with a slight and indistinct ridge, which is

* From its being furnished with plates on the back.

XYLOPHAGA. ].21

impressed by the line of demarcation between the striae on the
anterior side : pallial scar narrow, withdrawn and deeply
sinuated on the posterior side : muscular scars well marked ;
posterior oval and large ; anterior covering the fold of the
hinge-plate on that side. L. 0-375. B. 0-4.

Habitat : Oak, pine, and birch wood, submerged
between tide-marks or floating in the sea, on different
parts of the coast from Unst to Torbay. Although its
distribution is extensive, it has not been noticed in
many localities. I will therefore enumerate them. Tor-
bay (Turton) ; Exmouth (Clark) ; Gravesend (Crouch) ;
Scarborough (Bean and J. G. J.); Northumberland
and Durham coast (Backhouse and Abbes, fide Alder) ;
Marsden Bay on the Northumberland coast (Howse) ;
Bantry Bay and Waterford (Humphreys) ; Skerrie
Islands in the south of Ireland (Walpole) ; Dublin Bay
(Harvey and Warren) ; Loch Fyne (M f Andrew) ;
in dock gates at Ardrossan, Ayrshire (Martin) ; Moray
Firth (Macdonald) ; in a wooden shipping- stage at the
Whalsey Skerries, Shetland, and a single valve dredged
in 80 f., 30 miles north of Balta Sound (J. G. J.) . It
has also been taken at Drontheim in 30-40 f. by M f An-
drew and Barrett; at Drobak in 10-15 f. by Asb-
jornsen; at Bergen and Christiansund by Lilljeborg;
in other parts of Norway by Loven; on the coast of
Bohuslan in 22 f. by Malm ; in the Cattegat by Morch ;
at Brest by Dr. Daniel; in the Gulf of Lyons by H.
Martin ; and Professor Huxley gave me young speci-
mens which had penetrated the outer coating (tarred
hemp) of the Mediterranean electric telegraph cable on
the coast of Spain at a depth of from 60 to 70 f. ; some
of these last were about to attack the gutta-percha tube,
that formed the inner case or covering of the wire.
when the cable was taken up.

VOL. III. G

122 TEREDINID^.

This curious little mollusk attacks and injures sub-
marine timber, but not to anything like the extent that
Teredo does. Its burrow only extends \\ inch in
depth. The course of its perforation is diagonal or
slanting, and therefore is partly against the grain of
the wood. Its cell is flask-shaped with occasional con-
cavities, the edges of which are sometimes sharp to

receive the sides of the shell during the progress of the
animal.

It is the Pholas xylojihaga of Deshayes.
Family XXIV. TEREDI'NIDJE, Fleming.

Body worm-shaped and almost gelatinous, more or less
enclosed in a testaceous sheath, which is usually flexuous:
mantle very thin and cylindrical, enveloping the whole body,
open only for the passage of the foot at the anterior end, and
for the orifices of the tubes or siphons at the posterior end ;
it is folded back over the hinge of the shelly valves at the
anterior end, as in the Pholadidce ; and it adheres to the sides
of the sheath at the base of the pallial tubes, by means of a
muscular ring : these tubes are short in proportion to the
length of the body, but extensile ; they are united near their
origin, and forked towards their extremities ; orifices fringed
with short cirri : gills, a pair on each side, long, ribbon-like,
and distinctly laminated ; they are separate in front, adherent
for the greater part in the middle, and prolonged behind to
the base of the larger tube : palps consisting of two pairs,
short and pectinated : foot large, truncated, muscular and
expansile, not byssiferous ; it is attached to the rest of the
body by a thick and powerful cylindrical stalk.

Shell or principal valves placed at the anterior extremity of the
animal, helmet-shaped, equivalve, the valves touching each other
only at the hinge and in front, but elsewhere widely gaping :
each is divided and sculptured as mXylophaga: epidermis mem-
branous and thin : beaks not prominent, when viewed in front,
owing to their being inflected : hinge connected by the anterior
adductor muscle, which supplies the place of a cardinal liga-
ment ; it is covered by a thickened fold of the mantle, but
there arc no shelly plates or shields, such as the Pholadidce

TEREDO. 123

have ; the hinge is in articulated or jointress, although some-
times furnished with tubercular processes : apophyses falci-
form, springing outwards from beneath the hinge, one in
each valve : scars seldom distinct ; the posterior is large and
fixed to an ear-shaped expansion of the valve at that end :
pallets or bars (set in the muscular ring at the base of the
pallial tubes) paddle -shaped, with a narrow stalk ; the blades
are covered with an epidermis, and are either simple or com-
pound: sheath tubular, often nexuous, usually open at both
ends, and always at the posterior or outer end, which is
conical and has the throat lined with a series of slight con-
centric plates.

Nearly all these burrow in hard vegetable substances ;
none in stone. A species allied to Teredo (Kuphus
arenarius) , which inhabits tropical seas, lives in sand ;
its sheath is closed at the anterior or broader end when
the animal has attained its full growth. Deshayes,
Quatrefages, and Emile Blanch ard (all eminent physio-
logists) consider the Teredinidce a distinct family, on
account of their peculiar organization ; according to
Gray and the authors of the ' British Mollusca ' thev
ought to be comprised in the Pholadidm. The ex-
tremely elongated shape of the body, and its being en-
veloped in a testaceous sheath or cylinder, as well as
possessing a pair of paddle-shaped bars to protect the
tubes of the mantle, seem to be characters not less
important than those which distinguish any other two
allied families of the Conchifera.

Genus TERE'DO* Sellius. PL IV. f. 4.

Characters included in those of the family. All our native
species have simple pallets.

1. General remarks. — The "shipworm" of British

* A borer, from repeat

G 2

124 TEREDINID.E.

sailors, " taret " of Aclanson and the French, " zee-
worm '■' or " paalworm " of the Dutch, " see-wurm M of
the Germans, " troemark " of the Norwegian fishermen,
and formerly the " bysa " or " brnma " of the Italians,
and " broma " of Peter Martyr and the Spaniards. I
do not know any conchological study more interesting
and important, and at the same time more difficult, than
that of the Teredo. Although I have investigated its
natural history for many years, have carefully examined
a multitude of specimens, alive and dead, in order to
learn something of their habits and forms, and have
consulted perhaps every book or treatise published on
the subject, I feel as if I still knew but little of this
wonderful creature. Its biographers have been by no
means wanting for the last century and a half; so, like
the complete traveller in one of Bacon's essays, I " shall
suck the experience of many." The information I have
thus acquired, and the result of my own investigations
will be embodied in the following remarks ; and I hope
that other observers will take up the thread of my dis-
course, and make it more complete. The Teredo is an
anomaly. It consists of a long and nearly gelatinous
worm-like body, without rings or segments, termi-
nating at one end in a pair of hemispherical valves,
that somewhat resemble the two halves of a split nut-
shell which has had a large slice cut off at each side,
and at the other end in a pair of symmetrical shelly
paddles with handles of different lengths, which close
this extremity at the will of the animal. The open part
of the bivalve shell is placed at the further end, and
receives a circular disk, of a fleshy or rather muscular
nature, which mav be termed the foot : this is the
broadest or widest part. Inside each valve is seen a
curved process, like a bill-hook, that projects from the

TEREDO. 125

hinge at a right angle. The shell eovers and protects
the mouth, palps, liver, and other delicate organs. The
body tapers gradually to the outer or nearer end, where
it becomes quite small and attenuated ; it contains the
gullet, intestine, and gills, and is enveloped in a thin
membrane or mantle, which forms at the outward point
two cylindrical tubes, mostly of unequal length. The
larger tube takes in infusoria or similar animalcules,
which constitute the food of the Teredo, as well as im-
bibes water charged with air for the purpose of respira-
tion and keeping the whole fabric moist; while the
smaller tube is employed in the ejection of the water
which has been exhausted or deprived of its aeriferous
qualities, and also serves to get rid of the woody pulp that
is excavated bv the Teredo. Both tubes form a kind of
hydraulic machine. At the base of each lies one of the
paddles, often termed " pallets/' and which may be
translated into scientific language as " claustra."" When
the Teredo is alarmed, or not feeding, it withdraws its
tubes into the neck of its sheath or shelly cylinder ;
and the pallets, which had been previously kept pressed
against the sides, then spring forward and close the open-
ing, so as to form an efficacious barrier against all foes,
whether Crustacea or annelids. This complicated animal
mechanism is entirely enclosed in the sheath or cylinder
above mentioned, which is secreted by the mantle and
varies considerably in thickness and extent. The inside
of the sheath is at its outer or narrower end divided into
short strips or ledges, arranged in an imbricated fashion ;
the last-formed of these ledges serves as a point d'appui
for the blades of the paddles, and it greatly assists the
Teredo in closely shutting its doors. The whole of
what I have above endeavoured to describe is found only
within some hard vegetable substance, either the hull of

126 TEREDINID^E.

a vessel or boat, a harbour-pile, a shipping- stage, a float-
ing tree or the roots of one growing on the banks of an
estuarine river, a piece of balk timber, a fisherman's cork,
a cocoa-nut, a bamboo rod, a walking-stick, a beacon
or buoy, a mast, rudder, oar, plank, cask, hencoop,
or other ligneous waif or stray of the ocean. These
the Teredo perforates, like a rabbit or mole in the earth,
for the purpose of making its burrow and protecting
its soft and sluggish frame. It is never free, nor found
living anywhere except in its wooden gallery ; and it may
be cited as a teleological example. Without entering
much into the doctrine of final causes, I consider that
the Teredo shows an exact adaptation of means to the
end or object, viz. its existence. If it were not endued
with this or a similar power of self-preservation, it would
fall an easy and dainty prey to fish, crabs, and sea-
worms; and the race would be soon exterminated. Such
is the general aspect of the Teredo.

2. History. — The ancient history of this mollusk is
involved in much obscurity. Homer did not mention
in any of his works the word r€p7]Scov. It occurs for
the first time in the Knights of Aristophanes, where
the chorus reports a conversation that is said to have
taken place among some triremes, in which the eldest
of them declared to her companions that, sooner than
be engaged in a rumoured expedition, she would remain
where she was, grow old, and be consumed by Teredines.
Now as it was the custom of the Greeks, as well as of
the Romans, to lay up their vessels high and dry on
the beach, until they were wanted for service, the word
T€pr)8cbv, used by the great comedian, may have signified
the wood-boring grub of a beetle or moth, and not a
shipworm. Nor does it appear that Aristotle was ac-
quainted with it. The word is only to be met with once

TEREDO.

1:27

in his history of animals, when he describes the r€pi]ba)v
as a grub, which is bred in bee-hives. Possibly he
meant a young honey-bee. His TevOprjBcov (which
Casaubon incorrectly rendered teredo) is another kind
of bee. However, his friend Theophrastus, who suc-
ceeded him in the Lvceum at Athens, mentioned the
Tep;S&>v in such precise terms as to leave no doubt of
its being the mollusk in question. In the history of
plants, written by this great naturalist and philosopher
about 350 b.c, he restricted the name to a marine
destroyer of wood, distinguishing the terrestrial kinds
as o-fcwXrjfces and Opines, which may be designated
worms and grubs. His observations were made in his
native island of Lesbos ; and he says that the TeprjBcav
lives in the sea onlv, and is of small size but has a
large head and teeth. This description was probably
taken from Teredo minima. He remarked that wood
attacked by grubs might be easily restored and made
useful, by dipping it into the sea ; but there was no re-
medy for wood infested by the Teredo. In the same
restricted sense the word " teredo " was mentioned by
Ovid; and in his first epistle from Pontus occur the
well-known lines which were quoted by Sellius, and
were considered by Forbes and Hanley applicable to his
own sad case. The kind alluded to by Ovid was in all
probability the T. navalis of Linne, because after the
Crimean war I received specimens of this species,
which had been extracted from one of the Russian ves-
sels sunk at the entrance of Sebastopol. Pliny gave no
information of his own on the subject ; and even the
meagre account which he gleaned from Theophrastus
and others was very confused. Natural history was
at a considerable discount during the "dark ages;"
and the Teredo does not appear to have attracted the

128 teredinidtE.

attention of our remote ancestors. They were perhaps
too much engaged in waging open war with their neigh-
hour s, to notice the secret and insidious attacks which
the shipworm made on the few vessels which then tra-
versed the ocean. Literature of everv kind was con-

t/

fined to the cloisters of the monks, who had few oppor-
tunities, if any, of studying marine animals. A curious
piece of information, however, has accidentally fallen in
my way on reading one of the poems in the " Black
hook of Carmarthen," which, according to Mr. Skene,
a learned antiquary, was compiled or written in the
twelfth century, and is of unquestionable authenticity.
It seems to show that the Teredo was at that time in-
digenous to our seas. Yscolan, a monk and scholar,
gives an account in poetical and of course hyperbolical
terms, of a penance which he endured for some ecclesi-
astical offence ; and the following is a literal translation
of the lines : —

A full year I was placed

At Bangor, on the pole of a weir.

Consider thou my sufferings from sea-worms.

One kind of Teredo (T. Norvegica) is still found in
the stakes of fishing weirs on the Welsh coasts. After
the revival of letters Hooft, a Dutch historian, appears
to have been the first to notice the Teredo. He says
the dykes in Zealand had been destroyed by these
vermin before the close of the 16th century. We
learn from Johnston's ' Thaumatographia (Historise na-
turalis de Insectis/ 1653), that Drake's flag-ship was
found on his return from circumnavigating the globe to
be completely riddled by it. In the ' Ephemerides ' for
1666, Nitzschius recorded its appearance at Amsterdam
in ships which had been in the Indies, where it was
supposed to have originated. He describes the method

TEREDO. 129

adopted by the Portuguese to get rid of it. This was
to scorch their vessels, so as to form a crust of charcoal
an inch thick ; but he observes that the process was not
" sine periculo/' for it not unfrequently happened that
the fire would spread and the whole of the vessel be
burnt down. In the same century Bonanni and Daropier
briefly alluded to it ; but it seems to have escaped the at-
tention of Aldrovandus and Lister. In 1715 Yallisnieri,
and in 1720 Deslandes published some observations on
the subject ; those of the first-named writer were made at
Venice, of the other at Brest. In each case more fancy
than philosophy is exhibited. The " ver de mer " of
Deslandes w r as a fabulous production, compounded of the
Teredo and a well-known annelid which accompanies and
preys on it. He believed that some of these " vers de
mer " lived in wood, and others in the sea, and that the
latter copulated in the water and afterwards entered into
the wood, where the reproductive power ceased. One
remark of Deslandes is more correct, and at all events
is quaint. He says that it is difficult to imagine how
an insect, which has such a phlegmatic air, can be so
wonderfully active in its malice. In consequence of the
excessive devastations which Holland suffered from this
cause in the last century, and especially in 1730, 1731,
and 1732, the history of the " Zee-worm " w r as then assi-
duously investigated by a crowd of native writers, who
would seem to have been actuated by their patriotic
feelings ; and innumerable remedies were invented to
stop the plague. In 1733 eight different treatises, of
more or less merit, appeared. Preeminent among these
was a monograph by Godfrey Sellius, a celebrated
lawyer of Utrecht, and a fellow of our Ptoval Societv.
His ' Historia Naturalis Teredinis seu Xylophagi marini/
in quarto, contains 366 pages, besides two well executed

g5

130 TEREDINID.E.

plates. It is written in Latin. The work is a master-
piece of learned research, and replete with classical
allusions ; and it evinces far greater knowledge of the
organization of the mollusca than that shown by any
of his predecessors with the exception of Reaumur.
He describes the external shape of the Teredo, then its
internal structure, its peculiar habitat, the method of
its perforating wood, the arrangement and uses of its
different parts, its sexual nature and propagation, its
teleological relations, its history, name, and definition,
together with an explanation of its sudden appearance
on the coasts of Holland ; and lastly he details all the
recipes which were known in his time to prevent its
destructive operations, and he suggested others in addi-
tion. Nor did he share the erroneous notions enter-
tained by most of his contemporaries as to its place in
the animal kingdom. He proved that it was a true
mollusk, and closely related to Pholas ; and he insisted
on the advantage, if not the necessity, of studying the
animal as well as the shell — thus anticipating, by nearly
a quarter of a century, the much lauded views of Adan-
son in both these respects. He distinguished no less than
three European species, viz. his T. marina (which was
perhaps the T. navalis of Linne) , T. navium of Vallisnieri
(T. Norvagica, Spengler), and T. oceani of the same
author or T. megotara, Hanley. The subject appears
to have fascinated him, much in the same way as a
capricious mistress does her lover, who now deprecates
the cruelty of his fair tormentor, and then extols to the
skies her beauty and gentleness. He calls the Teredo
a wicked beast, the worst plague that angry Nature
could inflict on man ; but he defends it against the
calumnies of certain anonymous writers who had pre-
ceded him, and he expresses in enthusiastic terms his

TEREDO. 131

admiration of its symmetry, economy, ingenuity, social
harmony (especially in avoiding controversy and liti-
gation!), and its wonderful perfection in every par-
ticular. His account would almost persuade us that its
dwelling is a model for the architect, and its mode of life
a rule for the Christian. The observations of Sellius
with respect to T. navalis are so interesting, and on the
whole so correct, that I trust I may be here permitted
to republish some of them, although they are antiquated,
with such comments and explanations as I may deem
necessary. If the perusal should occasionally provoke
a smile, may it be one of charity ; and let the disadvan-
tages under which the Dutch naturalist laboured at the
time of his writing be fully taken into account. He
says that the Teredo varies greatly in dimensions, from
the minutest point to a foot or more in length, and that
specimens had been recorded which were even a foot
and a half and two feet long. The pallets (which he
styles iC pinnae ") are likewise of unequal size in dif-
ferent individuals, the larger ones being more soft, and
of a chalky consistency and dull aspect, not unlike
morsels of old yellow cheese; they are frequently
mutilated or distorted. The Teredo, when taken out of
the wood, soon dies, although it be immediately placed
in clear sea-water. This observation does not agree
with those made bv Professor Laurent in 1845 and
1847 with respect to T. Norvegica; and M. Eydoux
ascertained that the last-named species, after having
been taken out of the wood and kept in sea-water,
actually secreted and formed a new calcareous sheath,
although very thin and more or less incomplete, into
which the animal retreated, closing the larger end with
an hemispherical epiphragm (like those made by indivi-
duals in wood), and constructing at the smaller end two

13.2 TEREDINID.f:.

distinct apertures, for the passage of the siphons.
Quatrefages, too, extracted specimens of T. pedicellata
from their cases, and kept them alive in sea-water for
more than fifteen days. Experiments tried by Selliu
in putting Teredines into rain-water, beer, milk, and
similar fluids resulted (as might have been expected) in
their becoming feeble, and ultimately in their death.
The fecundity of the Teredo next attracted the atten-
tion of its biographer. He computed that the eggs
contained in a portion of one ovary were 1,874,000 (a
number exceeding the then population of the eight
chief cities of Christendom, namely London, Paris,
Amsterdam, Venice, Rome, Dublin, Bristol, and Rouen) ,
and that the entire ovary contained nearly seven times
as many, and considerably exceeded the population of
the seven United Provinces and all Great Britain to
boot. He minutely described the ova and fry, which
latter he found in different parts of the body. But
Quatrefages has recently investigated this branch of the
subject with very great care, aided by the light of
modern science ; and the result of these investigations
will be given in the proper place. The knowledge of
comparative anatomy possessed by Sellius was of course
somewhat imperfect. Perhaps the phrase which he
used in describing the ovary, " materia formatrix
ovulorum," is not recognized by physiologists of the
present day ; at any rate it is intelligible. Deshayes
has pointed out two or three more errors of this kind ;
but certain modern naturalists, whose opportunities
were far greater than those which Sellius enjoyed, have
committed mistakes of a not less grave character. I
need only allude to the published accounts of the
organization of Dentalium, as an instance of such inac-
curacies. Sellius goes on to say that the sheath is

TEREDO. 133

testaceous, and annulated or divided into ring-like
segments ; it is highly polished inside. The larger or
inner extremity is concave ; the other extremity is
conical. Adanson considered this appendage to be a
part of the shell. The Teredo is gregarious, although
not of a sociable habit ; and, in the prosecution of its
burrowing operations, it is actuated by a conscientious
anxiety not to infringe on its neighbour. When a
collision is imminent, it secretes a cup-shaped dome or
plug in front, of a thinner texture than the rest of the
sheath; and it shuts itself up. Sometimes it makes
several of these outer walls, one after another. Young
and old equally do this. It then, being unable to eat
its way through the w r ood and thus procure a supply of
food, dies of starvation, preferring suicide to the alter-
native of invading and injuring its companions ! This
sacred duty, he assures us, is performed with almost a
reverential care. He evidentlv considered his " hero "
(as he called the Teredo) the pink of chivalry and
honour. The wood is often so completely honeycombed,
that the party-walls which separate the burrows of the
Teredines consist of mere films. Rousset compared
the wood in this state to an extremely light and porous
kind of rusk or biscuit. Sellius stated truly the object
and mode of the curious dome-like fabrication which I
have above described ; but there was no foundation for
the consequences pictured by him, except in his fertile
imagination. The progress and further growth of the
Teredo would necessarily be arrested by the barrier
which it had interposed in front. But that was all.
The food of the Teredo consists entirelv of minute or-
ganisms, that are introduced with the water into the
incurrent or branchial tube ; and it does not consume
the wood as any part of its nutriment. Nor do I be-

134 TEREDINID.E.

lieve that the eroded material undergoes any chemical
change, either in the stomach of the Teredo or in the
passage outwards through its intestine, although in the
latter receptacle it is closely compressed. When it is
voided or expelled by the excurrent tube, and separated
in the water, it becomes a flocculent mass or pulp, like
that of paper, composed of extremely minute and fine
particles of an irregular size and shape, but still retain-
ing its fibrous structure. It does not exhibit any
appearance of having been digested. The notion that
the Teredo feeds on the wood which it excavates ori-
ginated in the lignivorous habit of the grubs of certain
insects. It was lately revived by Laurent to a qualified
extent. He tells us that the water, imbibed by the larger
siphon, holds constantly in suspension particles arising
from the decomposition of organic matter, as well as
living animal and vegetable bodies, and that these
particles, coming from outside, are united with the lig-
neous molecules which are produced by the wood being
rasped and continually softened or macerated by the
water, in order to form the usual food of the Teredines.
But, independently of what I have above stated with re-
ference to this question, the cases of Saxicava and the
Pholades must be considered. It can hardly be ima-
gined that these are stone-eaters. Sellius found that
the Teredo did not attack a pile below fourteen feet.
Further information is desirable as to the depth at
which it is capable of living. He observed that it
commonly follows the grain of the wood ; and that con-
sequently its tunnellings in fir and alder are straighter
and longer than in oak, which is tougher and more knotty.
It usually works round knots in a curved direction ;
but occasionally it drives right through them. The
odour emitted by the Teredo is different from that of

TEREDO. 135

the ovster and other shell-fish, and is derived from the
kind of wood in which it lives. I can answer for its
being very disgusting and almost insupportable. The
valves of the shell found in fir- and alder-wood are
white, almost pearly, and marked with pale ash-coloured
strise and dots; whereas those taken out of oak are almost
entirely yellow, sometimes of the darkest shade of black
with striae and dots of the latter hue. This remark
applies to the external surface only, and not to the
inside, which is uniformly pure white and pearly. The
pallets or " pinnae " have a yellowish tint, and their stalks
are invariably of the same colour and lustre as the inside
of the valves. The colour of the sheath varies in like
manner according to the kind of wood. The outside tints
appear to be extraneous, and not inherent in the Teredo
or secreted by it. Rousset having succeeded in keeping
Teredines alive in his own house, Sellius thought that
oysters, mussels, and other kinds of eatable testacea might
be profitably cultivated in tanks or reservoirs. A small
crustacean, called " Springertje " or " Snel >} (Limnoria
lignorum, Rathke), is generally seen in company with the
Teredo, and with its horny mandibles gnaws away the sur-
face of the wood. With regard to the mode of perforation
by Teredo, I have already stated the views of Sellius in the
f Introduction ' to the first volume of the present work.
I would, however, add that I am now inclined to differ
from him in the supposition that the adult shell is not
strong enough or adapted to rasp the wood. Cailliaud
has shown practically that this can be done ; and I have
lately repeated, with success, the same experiment. But
the improbability of the young or newly born shell being
able to effect a lodgment in this way seems to me as
great as ever. By examining the Teredo in situ, it will
be manifest that the foot is closely applied to the larger

136 TEREDINID.E.

end of the tunnel, and that it occupies the whole of the
front or hemispherical cavity. That part of each valve
which may be supposed to have a rasping power is
placed at the side, and not at the bottom. I believe
that the valves, instead of the foot, serve as a fulcrum,
and that they are pressed equally against both sides,
while the tissue of the foot is employed in absorbing
and detaching, slowly but gradually, minute par-
ticles of the moistened wood. If the shell were
the instrument of perforation, it would be applied to
the bottom, and not to the sides of the tunnel ; and no
muscle has yet been detected which could effect such a
change in the relative positions of the valves and foot.
Mr. Osier strongly advocated the theory that the wood
is rasped away by the shell ; yet he admitted that,
owing to the shortness of the lateral muscles in Teredo,
it was not probable that this mollusk could bore, like
the P kolas, by the action of these muscles alone.
Quatrefages agrees with Deshayes in considering the
muscular apparatus by no means adapted for putting
the valves in action as perforating-instruments, by either
a rotatory or a twisting movement. Pie attributes this
agency to the anterior fold of the mantle, especially
that part which lines the back or beaks of the shell
(called by him the ' ' capuchon cephalique ") aided by
continual soaking of the water, and perhaps also by
some secretion of the animal, as well as possibly by the
siliceous particles observed by Hancock in the mantle of
certain other perforating mollusks, and by Deshayes in
the integuments of the Teredo. But no part of the
mantle is placed in contact with the excavated end of
the tunnel or canal, which is entirely occupied by the
foot. In a memorandum which I received from the
late Dr. Lukis on this subject, he says (after summarily

TEREDO. 137

dismissing the chemical theory) , " Mechanical force
seems also scarcely probable or even possible ; for it is
not very evident how this can be employed whenever a
lateral opening is to be made in the side of the tunnel.
This opening is usually at some distance from the inner
or further end, and its edges are often very sharply
defined. If force were required to be exerted, these
sharp edges would be a serious inconvenience to the
Teredo, whose body is bent at this point into often con-
siderably less than a right angle ; such angles occur
more than once in the same specimen ." The marks at
the extremity of the tunnel, when examined under a
microscope, resemble in miniature those which are left
in mowing a grass lawn with a scythe ; but they are
arranged in a circular manner, and are continuous.
These marks are very numerous and narrow ; they do
not correspond with the anterior and striated part of
the valves, which (although rounded) are never bent at
such an angle as would produce the sharp lines exhibited
on the eroded cavity of the wood. The notorious fact
that the valves are covered with an epidermis is evi-
dently a stumbling-block in the way of M. Cailliaud;
because it would be difficult to understand why this slight
film is not rubbed oft", if the valves are used in scraping
the wood. He endeavours, with considerable ingenuity,
to dispose of the difficulty by assuming that the epi-
dermis is only formed temporarily and provisionally, to
protect the valves from the effect of the acid which the
Teredo employs in dissolving its sheath or outer case,
in order to make a new one. I am not aware that any
part of this assumption has been verified by observation.
M. Cailliaud was even unable to detect the presence of
any acid in Teredo, although he has given us a long list
of other mollusks which secrete it, including not only

138 TEREDINID.E.

Saxicava, Gastrochana, and P ho las, but also tlie common
oyster. I now take leave of this curious subject, be-
lieving that it has been sufficiently discussed or venti-
lated (" soaked " is the term which an English statesman
lately invented) ; and all naturalists, who take an inter-
est in it, may adopt whichever theory they prefer, be
it chemical, conchological, or malacological — in other
words, that the excavation is caused by the solvent
power of an acid, the rasping action of the shell, or the
sucker-like application of the foot. This is a very long
commentary, and I am afraid it will terribly "bore^ many
of my readers ; so I will resume the analysis of Sellius's
monograph. The quantity of water taken in and re-
tained by the Teredo is prodigious : Sellius not inaptly
compared the animal to an hydraulic machine. I feel
the same admiration that he avowed of the wonderful
sagacity shown by the Teredo in making its way through
a piece of wood, so as to avoid the tubes of other indi-
viduals. Every one pursues its own course with unerring
instinct ; and it must be gifted with some organ of sense
or apprehension, more delicate than we can conceive,
in order that it may be aware when it approaches an-
other Teredo. The sheaths are never contiguous, but
in every instance separated by an intervening layer of
wood. The Teredo uses its pallets as a means of defence
against its enemies, by closing the opening of the canal,

thus

" . . . . omnem aditum custode coronans."

He rightly described them as inserted in a sphincter-
like ligament at the base of the siphons. The function
of these processes is identical with that of the operculum
in many univalves — although they are not homologous,
or produced by similar organs. He next considered the
sexuality of the Teredo. His assertion that it is her-

TEREDO. 139

maphrodite (in which he followed Fontenel and Massuet)
has been within the last few years maintained by
Laurent, in opposition to the opinion of Quatrefages
that it is bisexual. The last-named author, indeed,
stated not only that the sexes are separate, but .that the
proportion of males was 5 or 6 out of 100 individuals
of T. pedicellata which he examined, the rest being
females. Baster had fancied, more than a century
before this, that coition took place between the Teredines
by means of their siphons ! Laurent informs us that he
found in an hermaphrodite gland of T. Norvegica eggs
and spermatic capsules at the same time, and that the
internal organization of the animal did not offer any
character to distinguish one sex from the other. I will
not pretend to decide such a controversy, which in all
probability concerns the whole of the Conchiferous
mollusca; but I have already (vol. i. introd. p. xxv)
given my reasons for concurring with Milne-EdAvards
in the belief that all the members of this class are
monoecious. The period of propagation, according to
Sellius, extends over the greater part of the year, even
as late as December, although the summer would seem
to be the most favourable season. In the month of
February he found the ovaries flaccid and emptv.
Sellius states that the eggs are never produced inside
the wood, but excluded by one of the siphons. He
suggested that the latter might have a peculiar (we
may say strange) function, namely that of moistening
the outside of the wood, and agglutinating the eggs to
its surface, or even excavating minute holes in it for the
purpose of assisting the fry in effecting an entrance.
He was also mistaken in supposing that the fry were
hatched only when the eggs adhered to the wood. It
has since been ascertained that this process takes place

140 TEREDINID.E.

inside the mantle of the Teredo, and that the fry are
ejected into the water in a larval or metamorphic state.
He was not aware that the fry have eyes and can there-
fore select their own habitat ; ,or he would not have
attributed their position in the wood to the maternal
care of their parents, under the idea that they are at
the mercy of the winds and waves. Massuet, moreover,
had previously put forth a notion that the fry crept
about the surface of the wood, and sought out convenient
spots where they could burrow. Our author observed
that the Teredo, in its earliest stage, underwent a kind
of metamorphosis by the method called "epigenesis/'
which is now recognized by most physiologists. This
remark is followed by an inquiry into the mystery of
Creation, in which he discusses the common opinion of
certain neoteric writers of his time that all living beings
had descended from original forms or types. The soli-
tary nature of the Teredo was not overlooked bv him.
Although surrounded on every side by companions, it
has no means of communication with them. Each lives
alone in a crowd. Nevertheless Sellius gives his fa-
vourite credit for a generous and unselfish disposition,
which its fellow creature, man, might well endeavour to
emulate. Nor did the Dutch philosopher exhibit less in-
dustry in his examination of the nomenclature of Teredo.
He ransacked the works of manv a classical author and
naturalist, from Plato and Aristotle to Oppian and Reau-
mur, with a view to elucidate its history; but he appears
to have got rather bewildered by the gossip of Pliny, who
confounded the Teredo with the grub of an insect. Sellius
did not share the credulity of some of his contemporaries
in supposing that T. navalis was introduced into Holland
by vessels (or in any other way) from foreign parts ; for he
unquestionably knew that the European species are diffe-

TEREDO. 141

rent from those which inhabit tropical seas. Although
the Dutch shipworm also infests the coasts of the Crimea,
there is just as much reason for believing that it had been
imported from the German Ocean into the Black Sea,
as that it had been exported in the opposite direction.
Linnets assertion, made seventeen years after the publi-
cation of the work now under consideration, that the Te-
redo was " ex Indiis propagata," had no other foundation
than common rumour. He ought to have known bet-
ter. Sellius, however, was inclined to suspect the recent
origin of Teredo, as a native of the German Ocean, and
to agree with his pious countrymen that it was a scourge
in the hand of an offended Deitv, and inflicted on them
for their sins. It is mentioned bv Smollett, in his
chronological medlev of home and foreign news, called
a ' History of England/ that in 1732 " the Dutch
were greatly alarmed by an apprehension of being over-
whelmed by an inundation occasioned by worms, which
were said to have consumed the piles of timber work
that supported their dykes. They prayed and fasted
with uncommon zeal in terror of this calamitv, which
thev did not know how to avert in anv other manner.
At length thev were delivered from their fears bv a
hard frost, which effectuallv destroved these dangerous
animals." Among the enemies of the Teredo, which
serve to check its increase, Sellius enumerates the
smaller fishes, which prey upon the fry in their free
state, and many insects (annelids and Crustacea) which
attack and devour the adult. Foremost among the
latter class of natural foes he ranks the Nereilepas (or
Lycoris) fucata, which he calls a marine Scolopendra.
This is frequently found in the empty canal of the
Teredo, of which it has taken possession, after insinua-
ting itself and clearing out the original occupant. His

142 TEREDINID.-E.

account of the voracity of N. fucata is confirmed by a
most valuable and instructive report presented to the
Academy of Sciences at Amsterdam, in I860, by Pro-
fessor Vrolik, the Secretarv of a Commission which
was appointed to inquire into the natural history of the
Teredo and the best mode of preventing its ravages on
the coasts of Holland. It was there stated that the
larvse of the Nereilepas and Teredo live together ; and
it is probable that, instead of the annelid entering in
an adult state the canal of the shipworm, as Sellius con-
jectured, it deposits its eggs in the open siphons of the
latter, whence they afterwards find their way into the
body and are developed. The larvae of some dipterous
insects have been also observed by Dr. Verloren, as well
as Sellius, to prey on the Dutch shipworm. Cochleo-
c tonus vorax disposes in nearly a similar way of cer-
tain snails. I have seen shells of Helix strigella and
H. incarnata, each of which was occupied by a grub of
that beetle, coiled round in a spiral shape like the
snail which it had supplanted. The name of the artifi-
cial remedies which were known at the time when
Sellius wrote was legion. He reckoned about 600
kinds of ointment, or preparations of an oily nature;
and he proposed one, which we now call creosote, to
penetrate the pores of wood by some hydrostatic power,
and which would have the effect of hardening and pre-
serving the timber. He had no faith in the efficacy of
any poison, being fully impressed with the idea that the
Teredo feeds on wood only; nor did he believe that,
even if this were not the case, the wood could be sa-
turated or imbued with poison by the most expensive
process that it was possible to discover. A thick and
durable coat of varnish, applied to the surface of the
wood, was in his judgment the best preventive, because

TEREDO. 143

it would keep out the fry. He especially noticed a
balsam of wonderful virtue, and kept a secret, which was
patronized by Peter the Great. Possibly this was the
resin now extracted by the Cochin Chinese from a gi-
gantic tree called "cav-dan" and lately noticed bv
M. Mariot, a lieutenant in the French navv. Native
canoes, hollowed out from the trunks of this kind of
tree, are said never to be worm-eaten. Among other
means of protection that had been long in use and
were still in vogue in his day, were the following : — for
ships, an inner layer of calf-skins, cow-hair, pounded
glass, ashes, glue, chalk, moss, or charcoal; for piles,
large iron nails driven in close together ; and for both,
hard and close-grained woods. By the first of these
methods, however (which is still partially made use of
by the Turks and Arabs in the Mediterranean), the
ship's course was apt to be retarded; and the latter
remedy was expensive and not always efficacious. He
said that the application of pitch or coal tar to the sur-
face of the wood had been recommended bv a Londoner
of some repute. We find in the ' Philosophical Trans-
actions ' for 1666 an announcement by an anonymous
writer that " a very worthy person in London suggests
the pitch, drawn out of sea- coals, for a good remedy to
scare away these noisome insects." The late Lord
Dundonald little suspected that the boasted discovery
of his father had been so long forestalled. Nor did
Sellius overlook the patent, granted by Act of Parlia-
ment in the reign of Charles II. (1671) to Sir Philip
Howard and Major Watson for preserving the hulls of
ships from worms by a sheathing of lead mixed with
some other metal, a composition now superseded by
copper. The conclusion arrived at by Sellius was
that the surest remedy consisted in trying to propitiate

1-44 TEREDINID.E.

the wrath of the Almighty by constant prayer and
praise. Many succeeded Sellius in investigating the
natural history of the Teredo ; but Adanson, Home,
Montagu, Deshayes, Quatrefages, Laurent, Clark, Fis-
cher, and Harting are perhaps all whose observations
are worthy of being noticed. If I have omitted the
name of any other writer, I offer by anticipation the
most ample apology for my neglect.

3. Habits and organization. — The opportunities which
I have had of examining this villanous animal (as Massuet
calls it) , and of observing its habits, were not so many as I
wished ; but I will relate faithfully what I have witnessed.
On my return in 1860 from the Continent, through
Holland, I had the pleasure of meeting Dr. Verloren at
Utrecht, and of carefully inspecting at his house living
specimens of T. navalis, enclosed in pieces of the dyke-
piles, which he had kept in long glass jars for about ten
months. They appeared to have become habituated to
the loudest noise ; and even when the jar was moved, or
the light suddenly obstructed, they did not withdraw their
terminal tubes or siphons. The longer (or alimentary
and incurrent) tube was in frequent motion, and bent in
various directions, as if in search of food, while a current
of water, full of animalcula, continually passed into it.
The shorter (or feecal and excurrent) tube performed its
functions at intervals, expelling the woody pulp by a spas-
modic action, and occasionally withdrawing, in order the
better to effect its purpose when any stoppage occurred.
Each tube was transparent, and fringed with cilia at its
orifice. The Teredines seemed to prefer the sunny side of
the jar; they are said to be very sensitive to cold. But
the most interesting peculiarity which I observed, and to
which my attention was directed by Dr. Verloren, was
that each of the tubes was protected or enveloped exter-

TEREDO. 145

nally by a very thin, pellucid, and film-like membrane
or sheath. These tube-sheaths are irregularly annular,
like the testaceous sheath or case which lines the exca-
vation in the wood ; and thev bear a considerable re-
semblance in shape to the stem of Tubularia indivisa,
though differing from it in texture and colour. The
sheath of the alimentary tube is about an inch long,
and the other is half that length. Their annular struc-
ture evidently arises from successive accretions of growth.
The use of these membranous sheaths may be either to
prevent the delicate tubes, which they cover for about
half their length, being choked or obstructed by the
accumulation of the flocculent pulp lying outside, or
else to protect them from the attacks of minute preda-
cious animals. Thev are renewed from time to time :
and in one of the specimens two separate pairs of these
membranous sheaths were attached to the outer opening
of the testaceous sheath in the Avood, one pair having
been apparently disused and a new set formed. The
Teredines grow and multiply with astonishing ra-
pidity. Quatrefages has given us an instance. A ferry-
boat plying between two villages on the opposite sides
of the mouth of Guibuscoa harbour in the Bay of Pas-
sages, on the north coast of Spain, was accidentally
sunk in the beginning of spring. Tour months after-
wards some fishermen raised the boat, hoping to make
use of the materials. But in this short space of time
the Teredo (T. pedicellatd) had made such ravages, that
the planks and beams were quite worm-eaten and de-
stroyed. Sailors have given me some interesting ac-
counts of hair-breadth escapes which they had, while
engaged in boat duty for a few weeks at a time on
foreign stations, in consequence of the paint having been
rubbed off the sides of the boat below the water-line :

VOL. III. H

146 teredinidjE.

wherever this was the case the ship-worm got in, and
speedily reduced the thickness or strength of the plank
to little more than that of an egg-shell. I have not un-
frequently noticed crowds of very young individuals in
a small and thin strip of deal, which could not accom-
modate any one of them if it grew larger : in fact each
had gone to the very end of its tether; and another step
would have laid bare its foot, and thus have exposed the
most vulnerable part of the body to its rapacious enemies.
Not having room to grow, or the power of removing to
a larger piece of wood, all these individuals must neces-
sarily perish without arriving at maturity. This fact
apparently illustrates a law of nature, which might be
termed blind ; but it may also be regarded as one of the
numerous methods by which various races of animals
and plants are kept under, so as to prevent an excessive
multiplication of any of them to the exclusion or detri-
ment of the rest. If no such checks were imposed, all
the wood on the face of the earth, if placed in the sea,
would probably not suffice to contain the Teredines
produced in a single year. The natural span of life
allotted to the Teredo is unknown to us : perhaps it may
be ascertained by means of the aquarium. It is supposed
that they attain their full growth in the course of a
few months. Extreme cold is fatal to them. Accord-
ing to the observations of Quatrefages on the north
coast of Spain, nearly all appear to perish in the winter ;
a few only survive to continue the breed. Vrolik be-
lieved that they hybemate on the Dutch coast. Warm
and drv seasons are favourable to them. In Holland,
where their proceedings have been watched with so
much anxiety, it was noticed that the greatest ravages
are made in July and August, and that the most de-
structive years during the last and present centuries were

TEREDO. 147

1731, 1770, 1827, 1858, and 1859. Very little rain fell
in those years. Laurent showed that thev are suffocated
and destroyed by oil being poured on the water in a
vessel containing Teredines in a piece of wood. He also
proved that they could not live in the " Salines ■' at
Hieres, too much salt being as injurious to them as
fresh water. But it appears that certain species
live in brackish or even fresh water. The T. Sene-
galensis of De Blainville was discovered by Adanson
in the roots of the mangrove and another kind
of tree lining the banks of the Niger, Gambier, and
other rivers on the west coast of Africa, which were
only subject to an influx of sea- water for a few months
in each year. According to Adanson the water of these
rivers is quite fresh or sweet during the remaining
months ; and T. Senegalensis not only exists, but re-
tains its full vigour throughout the whole year. This
statement, however, must be received with some quali-
fication. I am told by Dr. Welwitsch, the great botani-
cal traveller, that in the tidal rivers of South Africa the
water in the middle of the stream is fresh, while that
on the sides is brackish, and that no kind of mangrove
has been known to live in fresh water. Another sort of
shipworm [Nausitora Dunlopei of Perceval Wright)
has been lately found in India, inhabiting the river
Comer, one of the branches of the Ganges, and a per-
fectly freshwater stream, that returns to the main river
at a distance of about 70 miles from the sea. Dr. Kirk,
the friend and companion of Livingstone, informs me
that he picked up a piece of ebony (Dalbergia me-
lanoxylori) on a sandbank in the Zambesi river, the
water of which was there always fresh and drink-
able, 100 miles from the sea — very far beyond the in-
fluence of the tide, which never comes above 10 miles

h2

148 TEREDINID.E.

up the creeks of the delta. This piece of ebony was
pierced in all directions by a species of Teredo having a
calcareous sheath. The kind of wood mentioned by
Dr. Kirk resembles the ebony of commerce, but is
utterly worthless, except as fire- wood ; and therefore it is
not at all likely that the piece in question could have
been accidentally brought inland, after being perforated
in the sea by the Teredo. It sinks in water, is rather
brittle, much harder and far more compact than either
mahogany or teak, and is full of some mineral matter
that quickly deadens the edge of any tool. It does not
grow on the coast, nor within 50 miles of it on the
Zambesi. Dr. Kirk adds that in the bottom planks of
the pinnace belonging to the expedition the shipworm
was also found, with its soft parts attached to the finely
sculptured valves. The boat was so riddled that the
quartermaster pushed a paint-brush through her double
planks. This was at Tete, 250 miles from the sea, after
the pinnace had remained there six months at anchor.
I regret not having space to give in extenso Dr. Kirk's
interesting account of all the circumstances connected
with this discovery. Unfortunately the specimens were
lost on the way home ; but not the slightest doubt can
be entertained that the Teredo observed by him inhabits
water which is at all times perfectly fresh and sweet.
The habits of the Teredo are littoral. When they are
met with far from land, the piece of wood which contains
them has been accidentally detached and carried out to sea
by some marine current. Dr. Lukis noticed that, at Sark,
T. Norvegica and T. pedicellata pass more than half
their time out of water, during the recess of each tide,
when the shipping-stages in which they live are left
high and dry. Sir Everard Home confirmed the obser-
vation of Sellius, by saying that " the worm appears

TEREDO. 149

commonly to bore in the direction of the grain of the
wood, but occasionally it bores across the grain, to avoid
the track of any of the others." Although this is the
direction which it usually takes, it is bv no means un-
common to see perforations inclined at various angles,
and sometimes even made right through a tough knot
in a piece of oak. Montagu also remarked, with his
usual acuteness, that " the Teredo bores across the
grain of the wood as seldom as possible ; for after it
has penetrated a little way, it turns and continues with
the grain, tolerably straight, until it meets with another
shell, or perhaps a knot which produces a flexure ; its
course then depends on the nature of the obstruction ;
if considerable, it makes a short turn back in form of a
syphon, rather than continue any distance across the
grain." The same kind of siphonal bend takes place
when the piece of wood, being shorter than the average
length of the Teredo, is nevertheless broad enough to
admit of its abruptly turning and doubling like a coursed
hare. If the space is not sufficient for its complete
development, the Teredo shuts itself up and closes the
front with a cap-shaped epiphragm; it never pene-
trates that end of the wood, so as to make the canal
pervious. The Teredo possesses the same cartilaginous
styliform process which I noticed in the account of
P ho las. The imbricated plates, or septa, that line the
neck of the sheath in probably every species, serve as
ledges to support or strengthen the pallets, which are
withdrawn further into the sheath as the Teredo increases
in length and bulk ; the last formed plate is consequently
innermost. Fischer counted twenty-five of these plates
in a sheath of T. Norvegica. I do not agree with him
in believing that the Teredo goes on perforating the
wood beyond what is required for its habitation, nor

150 TEREDINID^.

that it abandons by slow degrees the narrower end of
the canal. The pallets of course increase in size rela-
tively to the growth of the body ; and as the sheath
enlarges inwards, new plates are formed in that direc-
tion to accommodate the increased size of the pallets.
Although the body is contractile to a certain extent (as
we see in dead specimens), it is fixed to the sheath by
the muscular ring which contains the pallets, and there-
fore cannot be withdrawn into the canal beyond that
line; the other extremity is employed in excavation,
until the canal has been completed. When a Teredo
has ceased to excavate before attaining its full growth,
and has interposed a barrier in front, its valves become
stunted and somewhat altered in shape, although their
sculpture is similar to that of ordinary specimens. The
same fact is observable in many other bivalves that in-
habit cavities or confined spaces, whether they are of a
boring or of a free nature. The cap-shaped plug, often
formed in front of the valves by individuals of every
age, serves as a partition wall between adjoining canals,
as well as indicates that the animal has ceased working; it
is formed like the sheath, but its substance is thinner.
Sometimes two or more of these plugs may be seen, one
after another, at various distances apart, as if the animal
had withdrawn and thus strengthened its inner line of
fortifications. Fischer Avas disposed to regard this secre-
tion as analogous to the epiphragm of land shells. That,
however, is only constructed for a temporary or occa-
sional purpose, and can be dissolved by the snail at
pleasure. It does not appear that the Teredo can do
this and resume its work of perforation. Laurent be-
lieved that the plugs or caps of the Teredo are made for
hybernation, an idea that is open to the same objection
as that of Fischer. The tubes or siphons, when in

TEREDO. 151

action and extended, diverge considerably ; so that the
excreta! tube discharges the exhausted water, faeces,
and woody pulp backwards, or in such a direction as
not to interfere with the current which passes into the
branchial and alimentary tube. Clark insists that the
anterior adductor muscle in Teredo, as well as in Pholas,
is a " genuine cartilage, which is a secretion from
glands." This notion is opposed to that of other phy-
siologists; and I merely mention it to show how difficult
it is for one not conversant with such matters to decide
the question, or even to understand how a cartilage or
ligament can be secreted in the manner suggested by
my late friend. He also stated that the pallets act as a
sort of force-pump, to facilitate the flow of water through
the long canal. M. Cailliaud supposes, on the other
hand, that the use of those appendages is to macerate
such food as is too bulkv to enter the tube. I cannot
accept either view. The one is hypothetical, and does
not accord with our knowledge of the nature of
the animal. The other assumes that the pallets lie
inside the alimentary tube, or at its orifice, neither
of which is the case ; they are placed at the outer
base of that tube, when it is protruded in search
of food. Valenciennes and Quatrefages consider the
posterior muscle to be that which attaches the pallet-
supporting ring to the sheath. Clark " perceived in the
centre of each plate a decided muscular impression/''
This I have not seen; but the posterior lobe or " auricle"
of each valve exhibits a scar, precisely similar to that
with which the corresponding portion of other bivalve
shells is marked ; and the muscle itself, connecting this
part in Teredo, is very strong and conspicuous. I
should be disposed to regard the muscle, which supports
the pallets and is attached to that part of the sheath, as

152 TEREDINID.E.

the homologue of tlie sinuated portion of the pallial mus-
cle in Pholas. In both cases it is placed at the base of
the tubes or siphons.

4. Embryology. — Nearly all our knowledge of this
part of the natural history of Teredo is derived from an
elaborate memoir by Quatrefages in the ' Annales des
Sciences Naturelles • for 1849. The process of oviposi-
tion is successive and of long duration. During a
period which varies according to the species, the female
emits her eggs, which are arrested and lodged in the
folds of the respiratory organs. In this singular nest
they are fertilized by the spermatozoa of a male,
disseminated through the mass of the surrounding
water, some of which find their way into the bran-
chial tube of the female, where they meet with the
eggs and vivify them by contact. The same me-
thod of impregnation takes place in Anodonta or the
freshwater mussel. The egg, while in the ovary,
consists at first of an extremely minute globule, which
is simple, homogeneous, transparent, and quite colour-
less. This is called " the vesicle of Purkinje." Some
very fine granules soon appear in the substance of this
globule ; and in a short time may be seen developed in
its interior a second globule called " the germinative
spot of Wagner." The two globules increase together
for some time before the formation of the yelk- mem-
brane which covers the whole. In this state the egg is
exactly spherical. Its volume then becomes enlarged ;
and after passing through other phases, it assumes
the shape of a tear, and when emitted the sphere is
converted into an irregular oval. The spermatozoa
now attach themselves to the egg, and certain internal
movements and changes ensue. These last for about
two hours ; the yelk- granules are distributed through-

TEREDO. 153

out the substance of the egg, and ultimately separate
into two nearly equal parts, one of which encroaches
by degrees on the other and at last completely enve-
lopes it. Towards the eleventh hour the yelk is trans-
formed into an agglomerative mass, composed of two
well-defined portions, and covered by a more or less
folded membrane. One of these portions now separates
into three lobes ; and vibratory cilia make their appear-
ance, at first short, thick, and few in number, after-
wards longer, finer, and much more numerous. The
cilia surround the entire body of the frv, which soon
swims with great rapidity, like one of the Infusoria.
This state lasts till nearlv the forty-eighth hour: then the
number of the cilia diminishes, and the fry falls to the
bottom of the vessel, where it moves rather slowly.
At the same time the yelk- membrane is divided into
two equal parts. These are the rudiments of the shell,
which at first is quite membranous, flexible, and irre-
gularly oval, with a salient angle at the point cor-
responding with the hinge. In a short time this form
is altered ; the salient angle is effaced, and superseded
by a re-entering angle. The shell is then symmetrical
and heart-shaped, and at the same time is encrusted
by calcareous salts and solidified. During the forma-
tion of the shell the mantle is developed, with delicately
ciliated edges, which are destined to replace the original
ciliary apparatus. The new cilia are extensible and re-
tractile, and consist of a single row. The fry can
withdraw entirely into their shells. At this stage they
appear not to be sensible of noises, nor even of an
agitation of the water in which they are placed. It
constitutes a critical period of their lives ; and a largo
proportion of the infantile community then perish.
About the sixty-eighth hour from the production of the

H

154 TERED1NID/E.

egg the cilia commence growing, and become stronger.
The duration of the last period of growth is miknown.
Some of the fry survived for 130 hours. The perfect
larva swims rapidly, like a Rotifer, and has a long, nar-
row, and strap-shaped foot — very flexible and resembling
that of a young mussel — by means of which it creeps
with apparent ease along the bottom of the vessel. It
remains for a long time suspended in the water by a
transparent filament from the sides of the vessel. The
shell then becomes nearly globular, instead of irregu-
larly oval ; a pair of red eyes are seen in the middle of
the body ; and otolites, or ear-stones, and other organs
are formed. The eyes afterwards disappear, the body is
elongated, and the animal assumes its complete form. I
have given the above description of Quatrefages nearly
in full, because it explains the embryogeny of the Con-
chiferous Mollusca in general. This eminent zoologist
is of opinion that the Teredo undergoes a true or complete
metamorphosis. In the first state of growth its integu-
ments are membranous ; it has no distinct organs ; its
sole mode of locomotion is by means of cilia, which cover
the body : it is a larva. In the second state it has acquired
a shell ; it possesses distinct organs of sense, besides a
special apparatus for swimming and a foot for creeping :
it is then a chrysalis or pupa. The third and last state
represents an imago ; the transformation has been com-
pleted, and the animal thus developed enters upon a
new phase of life, with appliances peculiarly adapted
to its altered conditions. In reality, however, the evo-
lution from a simple globule into a shell-fish endowed
^with a comparatively high degree of organization, and
of a complicated structure, is not the result of sudden
changes, but is effected by a series of successive growths,
or epigenesis. The outer membrane of the egg becomes

TEREDO. 155

a mantle, which, at first forms the shell and afterwards
the pallets and sheath ; the cilia, which invest most (if
not all) embryonic forms are absorbed, and a foot is
produced out of the firmer tissues of the body, and
substituted for the ciba; the eyes, mouth, palps,
stomach, intestine, liver, heart, gills, muscles, nerves,
reproductive and other organs come upon the stage
and play their several parts. " Instinct " does duty as
prompter. This, the inventive faculty of every creature
but man, provides for its necessities of food and de-
fence, and dictates the nature of its habits bv an in-
scrutable kind of prescience, that is little less than
divine. Laurent, Lukis, and others have also noticed
the great activity of the fry in their intermediate state ;
and M. Kater observed them swimming freely about
the piles in the dykes of Holland, and after a while
attaching themselves to the wood. Like the oyster-fry,
they seem capable, to a certain extent, of selecting their
habitat, and they probably use their eyes for that pur-
pose ; but this can only be the case when the sea is
unusually calm, their puny force being quite un-
equal to contend with any agitation of the water. I
have just re-examined a piece of wood to which some of
the fry of T. navalis still adhere. Each is no bigger
than the smallest pin's head, and is enclosed in a pair of
somewhat oval, close-fitting, semimembranous, and yel-
lowish valves, the only opening in which serves as a
passage for the foot or point of attachment. It bears
some resemblance to a minute Cy there or crustacean of
the Entomostracan kind, as well as to the pupa or last
larval state of a Cirripede. The original or rudimentary
valves are persistent, and form the umbonal portion of
the perfect ones ; they are easily recognizable in young
specimens by their different shape, consistency, and co-

156 TEREDINIDjE.

lour. A similar retention of embryonic parts occurs in
the case of beetles, the grubs of which do not part with
their horny jaws when they attain an adult state. It is
otherwise with the Lepidoptera, which exchange their
larval mandibles for a suctorial proboscis. The meta-
morphosis of Teredo is not less wonderful than that
which takes place in the frog, insect, or polype.

5. Structure of Shell. — The sculpture of the shell is
excessively complicated and delicate. Harting counted
4000 denticles in the anterior portion, and nearly 10,000
in the middle division of a single valve of T. navalis.
Dr. Carpenter kindly examined, at my request, the
microscopical structure of the valves and sheath of T.
Stutchburii. He informs me that the valves are ex-
tremely hard in texture, and that their substance has a
very peculiar arrangement, corresponding generally with
that of the shells of the bivalves most nearlv allied to it,
but having so special an adaptation to produce a fine
file-like disposition of the surface, that he cannot help
surmising there is more in the mechanical theory than
I am disposed to admit. The sheath is destitute of any-
thing like true structure, but has all the characters of a
mere exudation shell, formed of minute calcareous
particles, agglutinated together, very much like some
egg-shells. He adds that the difference in texture
between the two is nearly the same as that between the
half chalky substance of a crab's carapace, and the
almost ivory-like consistence of the black tips of its
claws. I would observe that the sheath of Kuphus
arenarius is remarkably solid and compact, with a
radiating structure, and that the surface of the shells in
some of the Pholadidce, and even in species of Tellina
and other genera, exhibit a file-like arrangement.

6. Origin. — An erroneous notion was formerly preva-

TEREDO. 157

lent that the Teredo had been originally introduced into
Europe from foreign parts — " calamitas naviuni ex In-
diis in Europam propagata," Linne, — which seemed to
be in some measure confirmed by its sudden appearance
in particular years. Even Mr. Osier, so late as 1826,
took for granted that T. Norvegica was not a native of
the British seas ; and he expressed his belief that, until
the general use of copper sheathing, it was probably
preserved only by occasional importations. But we now
find that each kind of Teredo has its own special area of
habitat. Tropical species will not live in the temperate
zone, and vice versa. That the Teredo is not of modern
origin in Europe is evident from the fact that T. Nor-
vegica, which at present is distributed over the North
Atlantic from Einmark to Sicily and Algiers, is also
found in both old and new deposits of our upper Tertiary
formation. T. megotara inhabits the coasts of Shetland,
and more northern latitudes in both hemispheres ; and
it occurs in a fossil state at Belfast and Uddevalla.
Deshayes first noticed the same fact with regard to T.
Norvegica being a fossil of the Italian tertiaries, as well
as of the Crag ; and it appears to be conclusive.

7. Distribution in the British seas. — Its distribution
along the British coast appears to be somewhat capri-
cious. Seaports, in which the admixture of fresh water
is considerable, such as Hull and Liverpool, are exempt
from the Teredo. But this rule has its exceptions.
The Medway is infested with the Dutch ship worm (T.
navalis), especially the upper reaches of the river, where
the water becomes less salt. I extracted living speci-
mens from the keel of a " watch boat/' kept at anchor
off Queensborough in that river for the purposes of the
lobster trade in the Billingsgate market. Milford
Haven has the Norway shipworm (T. Norvegica)

158 TERED1NID.E.

plentiful and of a large size. None of the other ports
in the Bristol Channel are troubled with that or any-
other species. The dispersion of mollusca is so wonder-
fully rapid, that in all probability a vessel wrecked any-
where on our coast, but not driven ashore, or a newly
erected submarine woodwork, will sooner or later attract
the wandering fry of some Teredo, which must have a
suitable nidus or prematurely perish. Or, as the whole
ocean teems with life in various states of development,
the germs of invertebrate animals (like the seeds of some
plants) may remain dormant for a long period, and only
become vivified when placed in favourable circumstances.
8. Economical relations to man. — The new Salvage
Act has somewhat interfered with the liberty of con-
chologists in searching the shore for Teredines. Mr.
Dennis was more than once baulked in his hopes of
examining a promising piece of driftwood, seen floating
towards Beachy Head, by the coastguard marking it
with the broad arrow directly it reached the shore. A
douceur is consequently necessary to secure the prize of
a honeycombed log. If Crabbe were a living poet, he
could not now say of the naturalist,

" His is untaxed and undisputed game."

The destructive nature of the Teredo is notorious ;
but we can hardly realize the extent of the damage
which these obscure miners perpetrate, by their stealthy
and incessant operations, when they attack our piers
and other submarine wooden structures. Quatrefages
asks us to imagine what would become of our trees and
furniture, and of the beams, joists, and rafters of our
houses, if they were to be gnawed by grubs measuring
a foot or more in length. However, no evil is unmixed
or without compensation. Smeathman, in his "Ac-

TEREDO. 159

count of the Termites" (Phil. Trans. 1781), remarked
that the seaworms appear to have the same scavenger
office allotted to them in the waters which the white
ants have on the land. It was also suggested by
Laurent and others that the Teredo might be occasion-
ally serviceable to us bv assisting in the removal of
wrecks, sunk at the entrance of harbours, which would
otherwise obstruct navigation. The celebrated Redi
describes it, in a letter to his friend Megalotti, as being
not only eatable, but excelling all shell-fish, the
oyster not excepted, in its exquisite flavour. Nardo
likewise praises the Teredo, although in less rapturous
terms : he wonders why the Venetians, who call it
u bisse del legno," do not eat it. I should, for my own
part, be surprised that any person having a stomach
could venture to try the experiment ; for the smell of
even a fresh shipworm is almost enough to turn one
sick. Ducks, however, seem to relish it, and not less
when it is in a half putrid state. As regards man, its
chief mission mav be

"To fill with worm-holes stately monuments"

of his workmanship. Perhaps it is one of the creatures
made not so much for our use as for our punishment.
Southey tells us that Bellarmine allowed mosquitos and
other small deer free right of pasture upon his corporal
domains, being more indulgent to them than to heretics.
He thought they were created to afford exercise for our
patience, and moreover that it is unjust for us to inter-
rupt them in their enjoyment here, when we consider
that they have no other paradise to expect. Yet when
the cardinal controversialist gave breakfast, dinner, or
supper of this kind, he was far from partaking any
sympathetic pleasure in the happiness which he im-

160 TEKEDINIDJE.

parted ; for it is related of him that at one time he was
so terribly bitten "a bestiolis quibusdam nequam ae
damnificis " (it is not necessary to inquire of what
species), as earnestly to pray that if there were any
torments in Hell itself so dreadful as what he was then
enduring, the Lord would be pleased not to send him
there, for he should not be able to bear it. Patience,
however, is not one of the cardinal virtues that we
practise ; and we therefore feel no compunction such
as Bellarmine had, but wage an incessant war of exter-
mination against the poor, not harmless Teredines.

9. Remedies. — Although our good neighbours the
Dutch have been the principal sufferers from this ma-
ritime plague, we have not been spared. In 1826
Mr. Osier believed that the Teredo, as a British animal,
was nearly and probably quite extinct. We should not
be sorry to find that this case of " dying out " had a
better foundation than many of those which have been
assumed by theoretical naturalists with respect to cer-
tain harmless mollusca. Unfortunately the ravages still
committed by this noxious mollusk in our harbours and
naval arsenals tell a different tale. In 1860 it was pro-
posed by a Committee of the British Association (of
which Committee I was chairman) to have certain
experiments made in the dockyard at Plymouth,
with a view to prevent the further destruction by the
Teredo of Government timber, which had cost the country
a considerable sum every year. A small grant had been
voted by the Association for such purposes. We find in
f Household Words } for 1857 the following statement:
" It has been estimated that at Plymouth and Devon-
port alone the boring worms have in one year destroyed
Government works to the amount of £8000." Per-
mission to have these experiments made was asked

TEREDO. 161

through the Port- Admiral, Sir Thomas Pasley, who ex-
pressed his entire approval, but forwarded the application
to the Admiralty. It is scarcely credible that no answer
was received for nearly a month, and that then came a
simple refusal without any reason given for it ! In
France and Holland special commissions have been issued
in the hope of discovering an efficacious remedy against
the attacks of the shipworm ; and experiments on an ex-
tensive scale are still being carried on in the last men-
tioned country. The preliminary reports which have ap-
peared (especially those of the Dutch Commission in 1860,
1861, 1862, and 1864) show the great pains taken to
ascertain as well the extent of the injury as the various
modes already devised to prevent it. Great Britain,
unlike other States, does not count a single naturalist
in her national assembly ; and the Government will not,
unless urged by popular pressure, take the initiative, or
even forward any plan of public improvement which is
out of the regular groove of routine. Few persons know
what a Teredo is ; and the general ignorance of such
subjects is too great for any except zoologists to distin-
guish this animal from wood-gnawing crustaceans, the
Limnoria and Chelura. We therefore ought not to
laugh at the ancients for confounding the shipworm
with the grub of an insect. With all of us the material
predominates over the intellectual. Wealth and its
companion luxury constitute our summum bonum ; and
knowledge is ignored.

" The world is too much with us ; late and soon,
Getting and spending we lav waste our powers ;
Little we see in nature that is ours ;
We have given our hearts away, a sordid boon ! "

It will of course be answered that there are other
things to be learnt besides the history of ship worms.

162 TERED1NID/E.

But is anything learnt now-a-days, save only the arts of
money-making and pleasure-seeking ?

In all probability the constitution of a shipworm is
poison-proof. Most of the remedies proposed in the
last century were of this nature, and they signally failed.
Quatrefages, indeed, has suggested that the production of
the Teredo might be checked by dissolving in the water
at the proper season a trifling quantity of corrosive
sublimate or acetate of lead, so as to destroy the sper-
matozoa or fertilizing agent. He tried some experi-
ments of this kind on a small scale in the harbour of
St. Sebastian. Quatrefages is an excellent naturalist,
and especially conversant with the natural history of
the Teredo ; but I fear his plan is not a practical one.
The Teredo attacks wood in the open sea, or in harbours
which the tide enters twice a day, and never in floating
harbours or wet docks, to which the tide has only
occasional access. Now, in order to prevent the birth
of the Teredo, which is always going on during the
summer months, it would be necessary that the tidal
harbour should be enclosed ; otherwise the poison must
be continually applied in prodigious quantities, and at
an enormous expense, or else it would be diluted to such
an extent by the action of the tide and waves (to say
nothing of the river which is generally indispensable as
a scouring power, and therefore flows through nearly
all such harbours) , that it would become too weak to
produce the desired effect. An eminent civil engineer,
Mr. Hartley, of Liverpool, recommended green-heart
timber to be used in harbours ; the costliness, however,
of that kind of wood is a serious objection to this re-
medy. Copper-sheathing and scupper-nailing are often
and successfully employed to protect piles in exposed
situations. The former is also expensive; and the crust

TEREDO. 163

of iron formed by the nails in the interstices between
them (unless they are very closely driven in so as to
completely cover the piles) is superficial and liable to
scale off*. I have known the Teredo bore through a
pile which was supposed to be protected by large broad-
headed nails in the usual way. At Christiania, in April
1863, I found that Teredo navalis was very destructive
to the woodwork in the harbour, and to boats lying at
anchor in the fiord. The chief engineer told me that
all the piles had been thoroughly creosoted (10 lbs.
to the square foot) before they were driven in, but not
to much purpose. Some were taken up while I was
there, and proved the correctness of his statement.
They had evidently been well saturated with creosote,
and yet were full of the ship worm. It seems that
these piles had been fixed only two years preAdously.
Another remedy that had been tried at Christiania con-
sisted in covering the outside face of the piles with
fascines of brushwood. This may partially succeed, by
excluding the light and warmth of the sun, and con-
sequently preventing the production or development of
the organisms on which the Teredo feeds. It certainly
does not love the cold shade. The maxim " obsta
principiis " is particularly applicable to the present case.
If we can succeed in preventing the young Teredo from
commencing its burrow, the wood is impregnable to its
attack. It is not difficult to bar its entrance when the
whole body is not the size of the smallest pin's head,
the foot almost microscopical, and the shell a mere film.
In this state it insinuates itself between the fibres of the
wood on the outside ; and having once gained a footing,
it works its way, slowly but surely, into the interior,
where it becomes snugly lodged and irremovable. It
is indeed a most troublesome guest ; and a line from

164 TEREDINID^E.

Ovid's l Tristium/ with the alteration of a single word,
will tersely express the difficulty of getting rid of it.

" iEgrius ejicitur, quam non admittitur hospes."

A very slight coating of any kind, applied to the sur-
face of the wood, will suffice to keep out the infant
burglar. Tar would answer the purpose ; but this
is liable to be accidentally rubbed off, or removed by
the continued agitation of the waves. Sir Gardner
Wilkinson informs us that the ancient Egyptians glazed
some of their inscriptions on stone, by covering them
with a vitrifiable composition, which was exposed to a
certain degree of heat, until properly melted and diffused
over the surface. Perhaps wood cannot be treated in
the same way ; but a liquid mixture, containing the re-
quisite ingredients, and capable of penetrating its pores
or fibrous texture, might be invented and applied to a
pile or the hull of a vessel. Any mineral preparation
that shall adhere firmly and permanently to the wood,
and not be subject to external influences, must be effi-
cacious. Such may be the silicate of lime, invented by
the late Mr. Ransome, and used for coating stone-work.
Every chemist knows that this is a manifest improve-
ment on Kuhlniamr's process, which consists of liquid
silicate of potash or " water-glass." Szerelmey pro-
posed an additional wash of a soluble bitumen, and
called the preparation " Silicat-Zopissa " ; but his ex-
periment has not yet been adequately tested. Zopissa
appears to have been a mixture of pitch and wax, first
used by the Phoenicians and Egyptians, and afterwards
by the Greeks and Romans, to preserve their merchant
vessels and men of war. The preparations of Ransome
and Szerelmey were tried in 1860 on part of the stone
facing of our Houses of Parliament, which had suffered

TEREDO. 165

considerable decay from being exposed to the corrosive
action of the London atmosphere, as well as from an
inherent defect in the material ; and time will show
which of these preparations is the best preventive. I
recommended Ransomed process in the discussion of the
Teredo question at the Oxford Meeting of the British
Association in 1880. Messrs. Peacock and Buchan
abont the same time invented and patented a composi-
tion for protecting wood-bottomed vessels from injury
bv marine animals. This is said to form by a chemical
combination with sea-water an unctuous or slimy pellicle,
and to succeed admirably in preventing the growth of bar-
nacles and similar incrustations by which ships become
fouled j but I am not aware of its utility with regard to
the present question. The popular notion is that the
barnacle and shipworm are the same animal, the one
being the part outside, and the other that which is in-
side the wood. Another remedy which has been pro-
posed, is to infiltrate the wood with silicate of lime ; but
I fear this would be too expensive for harbour piles.
Mr. William Hutton, of Hartlepool, has taken out a
patent of this nature. Although it was principally in-
tended to prevent the ravages of Limnoria lignoriim (a
small crustacean belonging to the class Isopoda, which
I have before mentioned) , it would also serve as a safe-
guard against the Teredo. Mr. Hutton's plan is to
harden the wood bv forcing it into a solution of silex
with muriate of lime. Perhaps the cost of his process,
but not its efficacy, might be lessened by applying the
solution in the form of a wash with a brush, instead of
infiltrating the wood by means of mechanical power.
The pores of the outer layer would probably be thus
penetrated to a sufficient depth, and the remedy be
equally complete.

166 teredinid^e.

10. Classification. — The mistakes made by some of the
older naturalists, and even by Linne, as to the organi-
zation and zoological position of Teredo, are scarcely
less remarkable than the object of which they treated.
In the first edition of the * Fauna Suecica/ published
in 1746, it was placed in Dentalium, along with that
shell and Serpula, the tube only being regarded. In the
tenth edition of the ( Systema Nature (1760), it was
correctly named Teredo ; but it was classed among the
"Vermes. Intestina," and described as having a mouth
with two jaws, inside which was a ciliated foreskin ("prse-
putium"), a siphon within the latter, and tubercles round
the mouth. In the twelfth and perfected edition (1767)
it is called a Terebella, and arranged between Serpula
and Sabella. These were unpardonable blunders on the
part of the great systematist, because in all his works
above cited he especially referred to the celebrated
monograph of Sellius, who had clearly shown the
affinity of Teredo and Pholas as testaceous mollusks.
Nearly a quarter of a century after the appearance of
that monograph, Adanson made the same observation ;
and his ' Histoire naturelle du Senegal * bears date
three years before the tenth, and ten years before the
twelfth edition of the ' Systema/ It is possible that
Linne had no opportunity of becoming acquainted with
Adanson's work on Senegal for many years after it was
published. The communication between Sweden and
France in their time could not have been so intimate as
it afterwards became. No such excuse however can be
offered for Lamarck's ignorance of the writings of his
distinguished countryman, seeing also that, at the date
of the ' Histoire Naturelle des Animaux sans Vertebres/
more than half a century had elapsed since the publica-
tion of Adanson's second memoir on Teredo in the

TEREDO. 167

1 Memoires de PAcademie Royale.' Lamarck described
the valves as containing a muscle which is protruded at
the posterior end, and the pallets as apparently bran-
chial ! Both O. F. Miiller and Fabricius had long pre-
viouslv adopted the views entertained bv Sellius and
Adanson as to the natural position of this mollusk ;
each in fact gave the only species known to him the
name of Pholas teredo. The familiar and appropriate
name of this genus has not escaped the experimental
handling of systematists. It is the Siphonium of Browne,
Xylophagus of Gronovius, and Teredarius of Dumeril ;
and it has been divided by other writers into minor and
more or less equivalent genera.

11. Indigenous species. — I propose to admit into the
list of British Mollusca only such species as inhabit
fixed and submerged wood on our coasts, and which of
course are really indigenous ; but I consider those found
in floating wood, and brought from distant parts of the
world, as no more entitled to be classed with native
productions than Hyalcea (Cavolina) trident ata, seve-
ral species of Ianthina, or Spirula australis, none of
which live in the British seas, although they are
occasionally drifted hither by the Gulf stream. Some
of the Teredines which pay us a visit in this way, reach
our shores in a fresher state than others ; T. megotara
frequently, and T. malleolus, T. eoccavata, T. bipinnata,
and T. cucullata now and then, have the animal entire,
although dead or scarcely alive, according to the length
of the voyage.

168 TEREDINIDiE.

Teredo Norve'gica*, Spengler.

T, norvagicus, Spengl. Skr. Nat. Selsk. ii. (1) p. 102, t. ii. f. 4-6 B, & 7.
T. norvagica, F. & H. i. p. 66, pi. iv. f. 1-5.

Body whitish, or of a light-greyish tint, seniitransparent :
tubes separated for about one half of their extent; orifices
encircled with fine cirri, which are longer and more numerous
in the incurrent or alimentary tube than in the other, and are
often of various colours, or edged with brown, red, rose, or
yellow.

Shell convex, solid and opaque, scarcely glossy ; it is
parted in the middle by a slight longitudinal crest, with a
broad but shallow furrow on the posterior side: sculpture
divided into three distinct portions, viz. anterior, middle, and
posterior: the anterior consists of sharp, narrow, and fine
transverse plates, from 60 to 80 in number, which are more
remote at first, and become closer in subsequent stages of
growth ; the edges of these plates are microscopically notched
across in an oblique direction ; this portion represents a triangle
having an acute apex at the beak of the valve, and a broad
and somewhat curved base : the middle portion extends the
whole length of the shell, and is strap-like ; the upper part
lies between the inner line of the anterior area and the crest
which separates one side from the other ; the lower part is
open outside, and bounded by the crest on the inner side ; the
broadest part is at the point of the angle where the anterior
and middle portions join ; this middle portion consists of
numerous extremely delicate and nearly equal stria?, the edges
of which are exquisitely beaded ; these stria? are longitudinal,
with an oblique tendency towards the posterior end, and they
diverge from the transverse plates at a right angle : the pos-
terior portion is always smooth, or only marked with concentric
and slightly raised lines of growth : colour whitish, with often
a tinge or stain of brown on the anterior side, especially the
separating line : epidermis membranous, yellowish-brown,
sometimes of a very dark hue : margins obtusely angular on
the upper part of the anterior side, with a large triangular
excision on the lower part, so that when the valves are united
in their natural position, the opening or gape is broadly heart-
shaped ; bluntly pointed or rounded in front ; and incurved on

* Inhabiting Norway.

TEREDO. 169

the posterior side, which, is terminated by a semicircular ex-
pansion, usually termed an " auricle ; ' in younger specimens
this auricle is entire, and has a high shoulder above, on a level
with the umbo, but in aged specimens the shoulder is worn
down by the continual attrition of that part, and a notch is
formed above ; dorsal margins sloping abruptly and equally
on each side : heals much incurved, situate near the anterior
end, at about one-third the length of the dorsal line ; umbones
or rostral portion prominent: hinge-line angular and irregular,
considerably projecting in the middle : hinge-plate very broad,
and extremely thick, folded over the anterior dorsal area, and
abruptly truncated and flattened, or occasionally excavated,
on the other side ; the centre is furnished with a callous
protuberance, as well as with a short peg-like tooth or
process, which is stronger and more conspicuous in the right
than in the left valve: apophyses very broad, and often jagged
at the edges : inside glossy, furnished in front with a rather
large and solid pear-shaped excrescence, and having the pos-
terior auricle separated by a strong ridge, which forms a
shelf or ledge in aged specimens : muscular scars large but not
strongly marked: pallets large; blades oval, wedge-shaped
and truncated or squarish in front, somewhat convex outside
and concave inside, of a laminated structure, and more or less
covered (especially at the outer end) with the same kind of
epidermis as invests the shell; stalks cylindrical, of a much
more solid substance than the blades, varying in length, being
usually about one-third the length of the blades ; the stalk
occasionallv extends into the blade at its narrower or inner
end, and appears like the midrib or nerve of a leaf: sheath
thick, sometimes indistinctly annulated ; septa or plates in the
neck of the sheath broad and imbricated outwards ; they are
divided near the opening of the sheath by a sharp ridge on
each side, which separates the branchial and excreta! tubes of
the animal, and is continuous in perfect specimens, so as to
form two distinct holes. Valves, L. 0*6, B. 0-65; pallets,
L. 0-8, B. 0-3 ; sheath, L. 12, B. 0-75.

Yar. divaricata. Shell stunted, distorted, and thicker, having
the anterior area much more developed than usual, and scarcely
any posterior auricle. T. divaricata (Deshayes, MS.), Fischer,
in Journ. Conch, v. p. 137, pi. vii. f. 7-9.

Habitat : In oak, fir, and birch wood composing the
timbers of sunken vessels, piers, shipping-stages, and

VOL. III. I

170 TEREDINID^.

gates of harbours and docks, as well as occasionally the
stakes of fishing- weirs, and submerged trees, all around
our coasts from Alder ney (Lukis) to Shetland (J. G. J.) .
It is, however, a local species. The variety is sometimes
met with. Fossil valves have been found in blue clav at
Belfast (Hyndman) , and in an oak tree dug up in exca-
vating a deep sewer there (Thompson) ; in a piece of wood,
more than twenty feet below the surface, at Ayr (Lands-
borough) : and sheaths in a fossil state have been found by
Mr. Grainger in the Belfast clay-beds, by Mr. Maw at
Strethill, and by Mr. S. Wood in the Red and Coralline
Crag. Newer Italian tertiaries (Soldani and Brocchi) .
The foreign distribution of this species extends from
Finmark (Sars, M'AndreAV, and Danielssen) to Algiers
(Deshayes) . It inhabits the boughs of trees laid down
in Kiel bay for the mussel-fishing (Meyer); and the
variety destroys, in conjunction with T. minima, the
fixed stages for shipping marble from the quarries at
Marola on the coast of Piedmont (Capellini) .

Olaf Worm first recorded it, in his ' Museum Wormi-
anum ; (1655), from Bergen. The pallets bear some
resemblance to battledores or to the bats of French
washerwomen; they are not unfrequently distorted.
Montagu fancied that the imbricated plates which line
the neck of the sheath might be intended to ensnare
the animalcula on which this Teredo feeds. He does
not say what kind of a trap they make. According to
Deshayes, Algerian specimens are much smaller than
those of Europe. Some sheaths at Port Patrick were
said by Mr. Thompson to have attained the extraordinary
length of 2| feet. I am not aware that this species has
ever been found in floating wood ; the specimens men-
tioned in the ' British Mollusca ' from this source, as if
on my authority, were the young of T. megotara.

TEREDO. 171

It is the T. navium of Sellius, T. navalis of Gmelin
and of almost every subsequent writer until Loven
identified that species with the T. marina of the first-
named author ? T. nigra of De Blainville, T. communis of
Osier, T. Bruguierii of Delle Chiaje, T. fatalis and T.
Deshaii of Quatrefages, and T. Senegalensis of Laurent
but not of De Blainville. The sheath appears to be the
Fistulana corniformis of Lamarck ; and I suspect that,
in one of the earliest stages of growth, it is the Denta-
lium bifissum of Searles Wood from the Coralline Crag,
the smaller opening of which exhibits the same internal
ridge or partition between the pallial tubes that is so
characteristic of this part of the sheath in T. Norvegica.
No Dentalium has any such process.

2. T. nava'lis*, Linne.

T. navalis, Linn. S. N. p. 1267; F. & II. i. p. 74, pi. iv. f. 7, 8, and
xviii. f. 3, 4.

Shell resembling that of T. Norvegica, except in being of a
much smaller size, and having a thinner texture and liner sculp-
ture : the posterior auricle in the present species is proportion-
ately larger, not placed so high up, more compressed, and better
defined both outside and inside (especially the latter) by means
of a thin overlapping plate, which separates the auricle from the
rest of the valve ; the colour also is fresh, although occasion-
ally deepened by an extraneous stain ; and the epidermis is
slighter : the pallets, however, exhibit the most remarkable and
characteristic difference ; the blade is oval and forked or
deeply indented and excavated in the middle at its outer edge :
the outside is slightly gibbous and glossy or prismatic, and the
inside is flat and of a dull chalky hue and cellular substance :
the stalk never extends into the blade ; and the pallets hi
this species are altogether more compact, and not laminar
as in the other species : sheath usually less solid in pro-
portion to its size, and more tortuous ; it is irregularly annu-
lated in young specimens ; septa or internal plates arranged

* Infesting ships.

i 2

172 TEREDINID.E.

close together, slight, and scarcely raised, but existing in all
perfect specimens ; siphonal or longitudinal ridge perceptible
only in the young ; aperture obliquely truncated in front, and
sometimes also at the back, making that part similar to the
slit end of a Dentalium. Valves, L. 0*3, B. 0*3 ; pallets,
L. 0-2, B. 0-1 : sheath, L. 6-0, B. 0-3.

Var. occlusa. Shell like the analogous variety of T. Nor-
vegica.

Habitat : (both the typical form and variety) in fir
wood or deal, composing the harbour piles at Sheerness
(Sir Everard Home), Heme Bay (Hanley), Yarmouth
pier or jetty (Rev. H. R. Nevill), Ramsgate pier
(Rev. Sir Charles Macgregor, Bart.); in elm stakes used
by fishermen for fastening their nets at Broadstairs
(Metcalfe); boats left long at anchor, and shipping-
stages in the lower reaches of the Thames and Medway
(Baxter) . It swarms along the European coasts from
Christiania (Asbjornsen) to Sicily (Delle Chiaje and
Philippi), as well as in the Black Sea (Pallas and Hein-
rich) and Oran in Algeria (coll. Deshayes); with T.
Norvegica in the boughs of trees, placed in Kiel bay to
collect the fry of the common mussel (Meyer); "Hell-
gate, New York, in a British frigate sunk during the
revolutionary war " (Tryon) .

This is the Dutchman's pest ; and he does not seem
to be troubled with any other kind, at least of the mol-
lusk tribe. It is extraordinary that the animal of such
a common species has never been described by any
author, except in a general way by Home and Vrolik.
Mr. Hanley procured some remarkably fine sheaths
from the pier at Heme Bay (supposed by him to belong
to T. megotara), which measure upwards of a foot in
length : for a couple of them I am indebted to his kind-
ness. They are much more solid than those taken from

TEREDO. 173

honeycombed pieces of wood, and have almost the po-
lish of ivory. Sometimes the pallets are distorted, and
the stalks are now and then double. The stalk passes
through the pallet ; but the upper part of it is seldom
visible, being covered by an accretion of the less com-
pact substance which forms the plate or main body of
this appendage.

It was first identified by Loven, and afterwards recog-
nized by Thompson and the authors of the ' British
Mollusca/ as the T. navalis of Linne. His description
was taken from the sheath only, and is so vague that
it may fit any species. Hanley remarked, in his
' Ipsa Linnaei Conchy lia/ as follows : " It is impossible
to determine, from the language of Linne, to what par-
ticular species of shipworm the very comprehensive
term navalis should be restricted. Our author has not
indicated the possession of examples ; consequently his
cabinet affords no assistance in the investigation." I
was inclined at one time to adopt the specific name
marina, given by Sellius, which is prior to navalis ; but
I now believe that the word " marina" was used by him
only as an epithet, in an opposite sense to " terrestris."
Linne, in the first edition of his ' Fauna Suecica/ de-
scribed the sheath as a Dentalium (in the index as Teredo
navis) ; and he adds that it is the T. navalis of Sellius,
and inhabits ships and submarine piles or stakes. In the
last edition of the ' Svstema Naturae ' the ' Fauna Sue-
cica' is quoted, and then Yallisnieri, Sellius, and Plancus.
The first and last of these authors intended T. Norvegica.
That species, as well as the present, still inhabits the
coasts of Sweden, as they probably did in Linnets time ;
and since the name Norvegica is free from any doubt,
and it is therefore advisable to retain it under the cir-
cumstances, there seems to be no alternative between

174 TEREDINID.E.

rejecting* altogether the time-honoured name navalis,
and applying it to the species now described. Da Costa
called it Seipula Teredo, Spengler T. batavus, Lamarck
T. vulgaris, and Van der Hoeven T. Sellii.

3. T. pe'dicella'ta*, Quatrefages.

T. pedicellatus, Quatref. in Ann. Sc. Nat. 3 e ser. (Zool.) t. xi. p. 26,
pi. i. f. 2.

Body not so long as that of T. navalis, and of a thinner
texture : tubes rather short, separated half way (Quatrefages).

Shell scarcely distinguishable from that of T. navalis. It is
always smaller ; the striae which cover the anterior area are
usually fewer, and consequently more remote, and the auricle
of the posterior area (especially in the young) is placed
somewhat higher up. The pallets however are unmistakeably
distinct. They are to a certain extent compound, and consist
of three separate portions. The stalk is very long and cylin-
drical : the blade or middle portion is roundish-oval, not much
raised, and flat below ; the upper part of the blade on each
side is dark brown or chocolate, and forms a strongly marked
band; it is laminated on the under side : the third or outer
portion is square, and is often notched or bifurcated like the
outer part of the pallet-blade in T. navalis, but never so
deeply nor excavated ; this third portion is sometimes ivory-
like, as well as the stalk and blade, and at other times yellow-
ish-brown, or of a horny substance. The sheath is thinner
and more decidedly jointed; and it is always shorter and
narrower than in T. navalis, showing that the animal
of the present species does not burrow so deeply. Valves,
L. 0.2, B. 0-2 ; pallets, L. 0-175, B. 0-05 ; sheath, L. 0-25,
B. 0-2.

Var. truncata. Corresponding with the varieties of the
preceding two species.

Habitat : Fir and oak used in submarine and fixed
woodwork at Guernsey, Alderney, and Sark (Lukis).
It was originally discovered by Quatrefages in the Bay

* From the long pallet-stalks.

TEREDO. 175

of Passages (province of Guipuscoa) on the north coast
of Spain; Tonlon (Eydoux and Gay); Provence (Martin,
fide Petit) ; Algeria (coll. Deshayes) .

Some valves which I received from the late Dr. Lukis
are of a greenish-brown colonr; these he found in oak.
He also sent me a piece of a deal plank, which had
formed part of a shipping- stage at Alderney, and had
been under water for twenty years : the outside was
fretted by Chelura terebrans ; the interior was full of
T. pedicellata ; and through their crowded galleries a
huge T. Norvegica pursued its solitary course, but with-
out interference on either side. The present species
produces at an early age. Its sheath is a beautiful
object, the points being imbricated like the segments of
the stalk of an Equisetum ; the orifice in very young
specimens resembles a key -hole. Dr. Lukis assured me
that this kind caused great destruction in the Govern-
ment works and new pier at Alderney : no endeavour
was made to prevent or stop it.

This is not a satisfactory species, because its sole dis-
tinction depends on size and the pallets, and it has
never been seen in company with T. navalis. The last
reason has, of course, a limited value, although it is by
no means unimportant when considered in connexion
with other circumstances and analogous cases. The
pallets are hoe-shaped, with a long handle, and a sepa-
rate shelly process or membranous fringe at the other
extremity. Fischer conjectured that T. pedicellata
might be the young of T. Norvegica or of T. navalis ; but
the pallets of each species, when first formed, exhibit
exactly the same relative characters as in subsequent
stages of growth.

176 TEREDINID.E.

4. T. mego'tara *, Hanley.

T. megoiara F. & H. i. p. 77, pi. iv. f. 6, and xvii. f. 1,2.

Bodv pale bluish- white : mantle not very thin : foot mus-
cular and coriaceous, attached by a thick and powerful cylin-
drical stalk (Clark).

Shell convex, solid, opaque, and rather glossy, parted in
the middle by a slight longitudinal crest, with a very broad
but shallow furrow on the posterior side : sculpture divided
into four distinct portions, viz. anterior, middle, furrowed,
and posterior : the anterior consists of sharp, narrow, and fine
transverse plates from 25 to 30 in number, which are more
remote at first and become closer at advanced periods of
growth ; the edges of these plates are microscopically notched
across; this portion represents a triangle having an acute
apex at the back of the valve and a broad and nearly straight
base : the middle portion extends the whole length of the shell
and is strip -like, the upper part lying between the inner line
of the anterior area and the crest which separates one side
from the other, and the lower part being open outside and
bounded by the crest on the inner side ; the broadest part is
at the point of the angle where the anterior and middle por-
tions join ; this middle portion consists of 15-20 extremely
delicate and nearly equal striae, the outermost of which are
exquisitely beaded, and the inner rows strongly but closely
notched across ; these striae are longitudinal, with an oblique
tendency towards the posterior side, and they diverge from the
transverse striae at a right angle : the furrowed portion is
marked with curved but not much raised transverse steps,
which gradually widen as they approach the front or ventral
edge : and the posterior portion is almost smooth or only
marked near the furrow by indistinct lines which form a con-
tinuation of the steps above mentioned : colour milk-white :
epidermis membranous, creamcolour, more persistent on the
anterior area : margins acutely angular on the upper part of
the anterior side, with a large triangular excision on the lower
part, so that when the valves are united the opening or gape
is broadly heart-shaped ; they are bluntly pointed or rounded
in front, and incurved on the posterior side, which is termi-
nated by a large compressed and rounded ear- shaped expan-

* Great-eared.

TEREDO. 177

sion, occupying at least one-half of that side, and raised above
the rest of the shell : beaks much incurved, situate near the
anterior end, at about one -third the length of the dorsal line ;
umbones prominent: hinge-line very irregular: hinge-plate
very broad and extremely solid, folded over the anterior dorsal
area, which represents a thickened sinuosity ; it is deeply
notched on the other side, in consequence of which the auricle
rises more abruptly; the centre is furnished with a large
callous protuberance or knob, as well as with a short peg-like
tooth or prong, which is stronger and more conspicuous in the
right than in the left valve: apophyses rather narrow and regu-
lar, not much curved, but occasionally twisted ; inside glossy,
furnished in front with a rather large and solid pear-shaped
excrescence ; the auricle is separated by a slight and indistinct
rib, but there is no shelf or ledge such as is observable in all
the other species before described: muscular scars distinct;
the muscles themselves adhere very closely, and can be easily
seen in living specimens ; anterior narrow and placed ob-
liquely across the centre of the hinge-plate ; posterior broad
and large, occupying about one-half of the auricle : pallets
large and leaf-like ; blade oval, squarish in front, slightly
convex outside and concave inside, covered with a glossy white
epidermis ; the outside front is wedge-like and partly ex-
cavated by a semicircular impression (exposing the laminated
structure of the blade), which extends inwards over one -third
or more of the blade ; stalk short, stake-like, more solid than
the blade ; it is continued on both sides far into the blade,
and on the under side may be traced the whole way from one
end to the other, like a midrib ; the upper surface of the
blade near the insertion of the stalk is sharply excavated on
each side, but not to any great distance : sheath usually thin,
except at the neck, which is lined with imbricated plates, and
these latter are crossed by a sharp siphonal ridge on either
side. Valves, L. 0-4, B. 0-4; pallets, L. 0-4, B. 0-15;
sheath, L. 3-6, B. 0*45.

Yar. 1. excisa. Shell similar to the stunted variety of each
of the foregoing species.

Var. 2. striatior. Shell more convex and not so solid ; an-
terior area larger, and more closely and finely striated ; hinge
callosity not so prominent.

Yar. 3. mionota. Shell smaller, with the auricle less de-
veloped and not reaching so far down ; pallets shorter, having
the semicircular part in front more deeply excavated.

i 5

178 TEREDINID^.

Habitat : Submerged woodwork at Wick (Peach);
fir wood at Lerwick and the Whalsev Skerries, Shet-
land;, in the first case composing the timbers of a sunken
vessel, in the other the supports of a shipping-stage
used in one of the fishing-stations there ; and also in
the hull of a small craft , lying at anchor in the Sker-
ries Sound, and employed by the Commissioners of
Northern Lighthouses on service between that place
and Lerwick (J. G. J.). These are the only cases in
which, to my knowledge, the present species of Teredo
can be said to be a true native of the British seas. It
is not unfrequently found in floating trees and pieces
of fir cast ashore on the east and north of the Shetland
Isles, after a continuance of easterly winds (having
been drifted from the opposite coasts of Norway);
in pieces of Canada timber, which apparently have
been transported by the Gulf-stream, aided by a succes-
sion of westerly gales, especially during each equinox,
on various parts of our shores including the Channel
Isles, Sussex, Devon, Dorset, Cornwall, Bristol Channel,
Galway, Waterford, Dublin, Antrim, Arran (in Scot-
land) , Scarborough, and Aberdeenshire ; in a piece of
oak thrown ashore in Cornwall (Couch) ; in the knee-
timber of a vessel stranded at Lulworth (J. G. J.) ; and
in teak, as well as in deal, at Guernsey (Lukis) . The first
variety only occurs in drift wood; Mr. Dennis found
some of a much smaller size than usual in a bamboo on
the Sussex coast. The second variety is also imported
from distant shores, and can scarcely be considered
British. The third may be referred to the same cate-
gory. Dr. Lukis noticed it at Guernsey, and Mr.
Dennis on the Sussex coast, in fir timber ; and a re-
markably stunted and minute form, in pieces of cork
(having been evidently once the net-floats of fishermen) ,

TEREDO.

179

has been taken at Plymouth by Mr. Webster, at Fal-
mouth by Mr. Norman, in Swansea and Carmarthen
Bays by myself, and at Aberdeen by Professor Macgil-
livray. This last variety was described by me as T.
subericola in the ' Annals and Magazine of Natural
History } for August 1860, under the impression that it
was a distinct species. The typical form and first two
varieties were detected by Mr. Hyndman in pieces of
drift wood, that were dug up in making a public sewer
at Belfast — thus showing the existence, at a period
antecedent to our own, of oceanic currents and other
conditions similar to those which still prevail. Malm
discovered a valve in the Udde valla deposits. This
species is widely distributed over the North Atlantic.
Torell found it on the west coast of Spitzbergen in drift
fir wood of two kinds, one from Norway or Siberia, and
the other probably from Canada ; Fahricius has recorded
it from Greenland, Mohr from Iceland (spoiling
valuable pieces of drift timber) , and Miiller from Norway
and Denmark; Lilljeborg found it at Mangesund,
Upper Norway, in the timbers of a sunken vessel, and
also at Bergen ; Deyenburg at Lysekihl, Bolmslau
(about 12 Swedish miles north of Gottenburg), with
T. Norvegica and T. navalis ; D'Orbigny (pere) at
Rochelle, Cailliaud at Croisic, and M f Andrew (var.
mionota) in the North Atlantic, in floating timber ;
Stimpson has described it (under the name of T. dilatata)
as infesting harbour buoys and fixed woodwork at Lynn,
New England; and Try on states that the range of this
species extends from Massachusetts to South Carolina.
The last-named locality affords some clue to a fact
which puzzled me not a little, viz. the occurrence in
drift wood of T. malleolus (a native of the West Indies)
together with the present species, which I received

180 TEREDINID.E.

from Dr. Lukis and Mr. Dennis. The proximity of
South Carolina to the Gulf of Mexico, and the course
of the great " river in the ocean " along the Atlantic
coasts of North America, indicated by Captain Maury
in his ' Physical Geography of the Sea/ may account
for this commixture of different kinds of Teredo in the
same piece of floating timber.

T. megotara is intermediate in size between T. Nor-
vegica and T. navalis, from both of which it may easily
be known by the large auricle on the posterior side and
by the strong and projecting hinge ; the pallets are more
like those of T. Norvegica, but they are flatter and of a
more delicate texture, with a semicircular impression in
front, and shorter stalks ; the sheath is of variable thick-
ness, and is sometimes altogether wanting, except at the
neck, which is regularly laminated with a siphonal ridge
down the middle of each side. The mouth of the sheath
in very young specimens is crossed by a slight and
curved rib, that separates the tube and resembles the
handle of a basket. A specimen which I took out of a
piece of Canada pine measured 21 inches from the
valves to the pallets.

I concur with the authors of the ' British Mollusca '
in rejecting the specific name nana, given by Dr.
Turton to this species; not only because it is inap-
plicable, but also because his description was insuffi-
cient and taken from immature and imperfect speci-
mens. At the same time I regret that the name which
they substituted for it is open to objection as pleonas-
tic or redundant, being compounded of two Greek
words signifying greatly and large-eared; megalota
would be more correct. It is the Bruma delV oceano
of Vallisnieri, T. oceani of Sellius, Pholas Teredo of
Miiller and Fabricius, T. navalis of Moller, T. dilatata

TEREDO. 181

of Stimpson, and (according to Fischer) T. denticulata
of Gray ; the young is probably P hoi as Teredula of
Pallas, from the coasts of Belgium.

Among the species brought hither by the Gulf-stream
from the shores of Northern and Central America, those
most commonly met with are

T. MALLEOLUS, TurtOll.

Valves white, elongated, and tapering towards the front ; the
auricle is narrow and wing-like, higher than the beak, and
projecting from the upper part of the posterior side : pallets
short, with a broad blade, which in the young is transversely
oval, giving a mallet- shaped appearance to these appendages :
sheath not long, but rapidly increasing in size ; it is thin, and
has delicately imbricated plates. Size of the valves nearly the
same as in T. Norvegica.

Habitat : Drift wood, Guernsey (Lukis) ; Torbay
(Turton); Exmouth (Clark); Sussex (Dennis); Swansea
and Carmarthen bays (J. G. J.); Miitown-Malbay
(Harvey); Belfast (Thompson); young, in cork, Ply-
mouth (Webster); Falmouth (Norman): Caiiliaud
found it also in drift wood at Croisic, Loire- Inferieure.
Specimens sent to me by Dr. Philip Carpenter for exa-
mination came from St. Vincents. I therefore infer
that the West Indies (and not Sumatra, as stated by
Forbes and Hanley) is its native place.

The valves (but not the pallets) of T. bipinnata, Turton,
apparently belong to the present species. As more
than one kind of Teredo often inhabit the same piece of
wood, mistakes are liable to be made in extracting the
valves and pallets ; such may account in a great measure
for the confusion that exists in public and private collec-
tions, and which has found its way into systematic
works. A specimen in the British Museum, named

182 TEREDINID.E.

" T. carinaia, Gray," is composed of the valves of
T. malleolus and the pallets of T. Stutchburii, De Blain-
ville.

T. bipinnata, (bipemiata) Turton.

Valves resembling those of T. mcgotara, but more convex
and of a thinner texture ; the striated strip is longer ; the
furrow is reddish-brown, delicately and closely marked across
with curved lines, and divided down the middle by a slight
groove ; the auricle is equally large and prominent, but does
not reach quite so far down as in that species, and it is sepa-
rated inside by a well defined shelf or ledge : pallets five times
the length of the valves ; blades composed of from 40 to 50
narrow funnel-shaped joints, set one within another, with
feathered edges which are fringed on each side ; stalk varying
in length (being sometimes only as long as the blade, and at
other times three times as long), quill-shaped, cylindrical, and
slender, minutely tuberculated, and often closely annular or
tracheiform towards the blade : sheath thick and solid, increas-
ing rapidly ; neck finely and closely wrinkled but not lami-
nated. Size of the valves about the same as in T. megotara.

Habitat : Drift wood at Guernsey (Lukis) ; Exmouth
(Turton); Beachy Head (Dennis); British Channel
(Bulwer); Scarborough (Bean); Roundstone, Conne-
mara (Walpole); Miltown-Malbay, Clare (Harvey);
Youghal (Ball); Waterford (Humphreys). On the
French coast it has been noticed at Cherbourg and in
the Gulf of Gascony by Fischer, at Pouiiquen by Petit,
and at Croisic by Cailiiaud. Dr. Philip Carpenter has
also recorded it from Vancouver's Isle and C, viiomia,
and I received specimens from him as West- Indian :
there seems to be no good reason for considering it
Sumatran. It occurs with T. cucullata.

Dr. Turton stated that the feathered pallets could be
ejected and retracted at pleasure, and that they were pro-
bably " instruments of absorption, as the animal is fur-

TEREDO. 183

nislied with a single terminal tube, whose office may per-
haps be the discharge or deposit of its eggs or spat ! " He
may have been, like Bellario, " a learned doctor/' each in
his own profession ; and we will charitably think that
the physician understood the constitution of his patients
better than that of the Teredo.

This species is the T. navalis of Spengler, T. bipinnata
of Fleming, and T. pennatifera of De Blainville. The
type examples of Spengler in the Royal Museum of
Copenhagen are composed of the valves of T. bipinnata
and the pallets of T. Stutchburii.

It is very difficult to say what the T. palmulatus of
Lamarck may have been. He described the pallets
only, which are • apparently the same as those of the
" Taret de Pondicheri/' figured by Adanson in the
' Mem. de FAcad. Roy/ for 1759. The habitat given
by Lamarck is " L'ocean de grandes Indes, les mers des
pays chauds/'

The less-known visitants are T. excavata from drift
fir, Guernsey (Lukis) and Sussex (Dennis); T. bipariita
from West-Indian cedar, Guernsey (Lukis); T. spat/ia,
with the last ; T. fusticulus from the same kind of wood,
at Leith (J. G. J.) These have simple pallets. T. cu-
cullata from drift fir, Guernsey (Lukis), and Sussex
(Dennis), and from teak, with the next species, Belfast
(Thompson); and T. fimbriata (T. palmulata, F. & H. i.
p. 86, pi. ii. f. 9-11, but not of Lamarck or Philippi)
from teak ship-timber, Belfast (Thompson); Exmouth
(Clark); and Leith (J. G. J.) . These last have compound
pallets. All the above (except T. fimbriata) were fully
described by me in the 'Annals and Magazine of Natural
History'' for August 1860. T. spat ha and T. cucuUata
are probably West-Indian, because I received from Dr.
Philip Carpenter for identification specimens of both,

184 TEREDINID.E.

which were found by the late Professor Adams at
Jamaica. T. fimbriata is said by Dr. P. Carpenter to
be a native of Vancouver's Isle.

T. minima of De Blainville is common in the Mediter-
ranean, but has not been noticed on our shores. It has
rather long and large close-jointed pallets with plain
edges; the valves are very much smaller than those
of any British species, and somewhat resemble the
stunted form of T. navalis. The pallets of this species
and T. fimbriata may be taken for miniature ears of
barley with long stalks. T. minima is the T. bipalmata
and T. bipalmulata of Delle Chiaje, T. palmulata of
Philippi, T. Philippii of Fischer, and T. serratus of
Deshayes's MS.

Having disposed of the headless mollusks, which are
represented by the classes Brachiopoda and Conchifera,
we next proceed to consider such as have a head. These
exhibit a greater diversity of shape and a more compli-
cated structure ; their organs and functions are more
specialized. Thus creation moves, step by step, higher
and higher, until at length that mental pinnacle is
reached, which is attainable only by the chiefest among
our own kind. In the suggestive language of Tennyson,

"All nature widens upward. Evermore
The simpler essence lower lies ;
More complex is more perfect, owning more
Discourse, more widely wise."

The first in order among the Cephalic Mollusks is a
peculiar class, partaking somewhat of the nature of the
Acephala, and forming a link between the two. It is the

SOLENOCONCHIA. 185

SOLE'NOCONCHIA*, (SOLE NO-
CONCHES) Lacaze-Duthiers.

Body cylindrical, gradually tapering to a rather fine point :
mantle sheath-like, contractile, thickened in front, where it
forms a circular collar, thin and membranous in the middle,
constricted behind and terminating in a short tubular process :
head small and indistinct, not visible outside, furnished with
a pair of horny jaws and a spinous tongue : mouth internal,
surrounded by labial palps : tentacles thread-shaped, long and
numerous, arranged in two bunches, one on each side of the
mouth; they are contractile and ciliated: gills rudimentary
and obscure, placed above the liver : foot remarkably flexible,
and divided into three lobes, the middle one of which is conical
and extensile ; it occupies the front and issues from the collar
of the mantle : posterior tube serving the purposes of a branchial
and excretory duct, as well as assisting in the work of repro-
duction.

Shell tubular and resembling an elongated funnel, more or
less curved, and open throughout, with the broader end in
front ; the narrower or posterior end is channelled and some-
times slit.

This small eccentric class comprises the "tooth shells/''
so called from their resemblance to the tusks or canine
teeth of some animals. Their nature in a zoological
point of view was but little understood until of late
years. Linne placed them in his " Vermes. Testacea ; ,}
Lamarck and Cuvier considered them Annelids ; De
Blainville and Deshaves restored them to the rank of
Mollusca. But the skilful and patient investigations of
Lacaze-Duthiers have at last solved a problem the interest

* From the tube-like shell.

186 SOLENOCONCHIA.

of which, in the estimation of a conchologist, surpasses
that of the still sought-for discovery of the sources of the
Nile. His "Histoire de F Organisation et duDeveloppe-
ment du Dentale " appeared in the ' Annales des Sciences
Naturelles ' for 1856 and 185 7, and is worthy of his
academical fame. His researches were prosecuted at
St. Malo; D. Tarentinum was the subject. He killed
and prepared the animals for anatomical dissection,
either with prussic acid, or by drowning them in sea-
water, particularly in that which contained the putrid
corpses of their late companions. In the delightful
' Sea-side Studies ' of G. H. Lewes will be found a
thoughtful discussion of the very difficult question
whether the simpler animals feel pain. He answers it
in the negative; and I agree with him to a certain
extent. A predaceous beetle with a pin through it will
eat up other insects confined in the same collecting-box •
and every part of a polype cut in pieces will flourish.
At all events the Invertebrata appear to be exempt from
that sense of apprehension, or anticipation, which we
regard as the worst pain. The Dentalium burrows in
sand by means of its conical foot in a slanting direction ;
the narrow end is of course uppermost, and is kept in
communication with the water or air for the purpose of
respiration. It feeds on Foraminifera and other minute
organisms, which it catches with its thread-like tentacles.
These are of all lengths and sizes, and are insinuated
among the grains of sand on every side; they are
covered with cilia, especially at the points, which resem-
ble suckers. They are thrown off by the Dentalium
under certain conditions, and may occasionally be seen
detached and wriggling like taper hair-worms. Tere-
hella and other tubular annelids have similar organs.
Being highly contractile, these tentacles convey the food

SOLENOCONCHIA. 187

to the funnel-shaped mouth, in which, by the aid of
labial and ciliated palps, the animalcula are quickly en-
gulfed : then the masticatory apparatus comes into
play. This consists of a tongue or lingual riband, armed
with five rows of sharp spines, one in the middle, and
two on each side. The central tooth is usually called
a " rachis/' and the side teeth " pleurae ; " they are ar-
ranged thus, 2.1.2. The front set of pleurae are armed
with crochets or " uncini." The apparatus now described
seems to have an office analogous to that of the tongue
in many cephalophorous mollusks, and it is certainly not
a gizzard as Mr. Clark supposed. The shelled Forami-
nifera found in the stomach of a Dentalium are perfect,
and the sarcode must be extracted from them bv some
secretion answering to the gastric juice of the Verte-
brata. Dentalium has no eyes ; they would be useless
to an animal always buried in sand. They have otolites
or ear-stones, which serve as organs of hearing ; these
are extremely numerous, calcareous and globular, and
are enclosed in two nearly spherical pouches lined with
vibratile cilia, which are in constant action, and agitate
the otolites by an incessant tremulous movement. The
organs of circulation and respiration are of a rudimen-
tary kind ; there is no heart. The sexes are separate.
There are no external organs of generation; but im-
pregnation is effected by the male emitting his sperma-
tozoa, and the female her eggs at the same time, in the
water. The process may be partly compared to the
chance shedding of pollen in the air by dioecious plants.
Lacaze-Duthiers noticed that the spermatozoa lived
six hours after performing the act of fecundation.
The egg is at first oval, afterwards pear- shaped, and
ultimately divided into segments like those of an Annelid.
Such eggs as do not arrive at maturity speedily decom-

188 SOLENOCONCHIA.

pose, and are cleared out by swarms of Infusoria, which
appear to be generated from the corruption. In the first
stage of development the germ is motionless ; in the
second stage it is propelled by vibratile cilia, which are
set round a large lobe in front, similar to that observ-
able in the larvse of many mollusca, and it swims
rapidly; in the third stage it crawls by means of a disk-
like foot. In swimming it does not come to the surface
of the water, as do the fry of the oyster and other
mollusca. The shell is formed during the third period,
but is only detected by its iridescent lustre, being
exceedingly thin and transparent, a mere film. This state
continues till the fifth and occasionally the sixth day after
birth. The embryonic period lasts from thirty-five to
forty days. If any of the fry die, Paramecia and Ploes-
conm (Infusoria) are bred from the decaying matter,
and, entering into the shells of living individuals, soon
destrov them. Lacaze-Duthiers observed a current of
water passing through the shell from the opening at the
smaller end. He discovered the Dentalium at low-water
mark, where its presence was betrayed by a small groove
in the sand ; and he seems to have got a knack of find-
ing them, for he says he easily procured 200 live speci-
mens at the recess of a single high spring tide. They pre-
fer certain spots, especially patches of coarse sand mixed
with broken shells and interspersed with Zoster a. In this
part of his researches he derived much assistance from the
hydrographical survey of France, the minute accuracy
of which he greatly praises, not merely as regards
zoology, but as subservient to the navigation of the
coast. I fear we cannot say so much for ourselves on
this side of the Channel, when we reflect on the shame-
ful delay that takes place in the publication of our charts,
and even now find that the hydrographical survey on

SOLENOCONCHIA. 189

the west of Scotland has been stopped. All we can
boast of is a long annual list of wrecks. We are a
people that have had losses ; like Dogberry, we can
afford them : but a superabundance of wealth will not
restore drowned mariners to life. The Dentalium is
hardy, and apparently abstemious. Lacaze-Duthiers
kept some alive in a flask of sea-water with a little sand
for more than eighteen months. It is much more active
at night, and sensible of light. A ray of the sun or the
flame of a candle will cause it to withdraw its foot.
This organ acts as a piston in expelling at the other end
the eggs and seminal fluid, as well as perhaps the fseces
and exhausted water. The point of the young shell is
pear-shaped, and bears some resemblance to a baby's
feeding-bottle with the hole at one end instead of in the
middle. It is broken off when too small to contain the
terminal tube or process of the mantle ; and this part of
the shell is continually rubbed away as the animal in-
creases in size, until at last it becomes truncated, and a
short pipe is formed with an oblique slit in front to
accommodate the terminal tube. The slit is extended
in certain species, although this distinctive character is
confined to adult specimens. The inside of the shell is
white as porcelain, and brilliant as varnish. The epider-
mis is slight and easily abraded. The microscopical
texture of the shell is scarcely different from that of
Patella. It is most complicated, being composed in a
great measure of prisms, interlacing fibres, and anasto-
mosing canals — not of cellular elements. The quantity
of animal matter which it contains is next to nothing.
From the above account, which I have mainly derived
from the memoirs of Professor Lacaze-Duthiers, it is
evident that Dentalium is an object well deserving the
study of conchologists. Thanks to him, its position

190 SOLENOCONCHIA.

among the Mollusca may now be considered settled.
Its symmetrical organization and habits connect it with
the Acephala ; its spinous tongue, indicative of a head,
allies it to the Gasteropoda. Its shell, although univalve,
is tubular and pervious, never corneal or spiral ; in all
these respects it differs from the shell of Patella, which
is never tubular or pervious, but always conical and
when young exhibits a distinct spire. Its relation to
the adult Fissurella is merely one of analogy. For
all these reasons I see no alternative but to adopt the
opinion of the learned French academician by making
it the type of a separate class. Argenville, in his
' Zoomorphose ; (1757), gave the first idea of the ani-
mal. De Blainville called them ' Cirrobranches/ mis-
taking the tentacles for gills. Deshayes and Clark un-
fortunately tripped after him ; and both appear to have
made several mistakes, although of a contradictory
nature, with regard to the anatomy of the animal.

" Velut silvis, ubi passim
Palantes error certo de tramite pellit ;
Ille sinistrorsum, hie dextrorsum abit ; unus utrique
Error, sed variis illudit partibus."

It is unnecessary to notice the attempts of other syste-
matists, who, so far from contributing anything to our
former minimum of knowledge, did their little best to
lead us also astray. I may add that the views of Lacaze-
Duthiers have been most satisfactorily confirmed by an
elaborate essay of Sars on his Siphonodentalium vitreum,
which is perhaps the type of a new family of the present
class.

DENTALIUM. 191

Family DENTALI'ID^E, H. & A. Adams.
Genus DENTA'LIUM* Linne. PL V. f. I.

See the account of the class for the characters of the family and genus.

We find in Aldrovandus that, according to Brasavolus,
the generic name was anciently " antale " or " dentale,"
the two names signifying a difference of size only. They
were not considered Conchse, being neither bivalves nor
univalves. Valerius Cordus called the larger sort an
" Enthalium," and the smaller a " Dentalium. v Some
persons ate them raw as well as cooked ; and druggists
sold the shells for medicinal purposes, believing them
to be of a mineral nature. Nicodemus Myropous put
the names into a Greek dress, viz. avraXi and rivraXc.
Martini distinguishes the " Antales \ 3 as being smooth,
and the " Dentales " as fluted and angular.

1. Dentalium en'talist, Linne.

D. entalis, Linn. Syst. Nat. p. 1263 ; F. & H. ii. p. 449, pi. lyii. f. 11.

Body milk-white : tentacles slender and extensile, with oval
tips : foot flanked on each side by an irregularly scalloped
lobe.

Shell tapering, not much curved, often irregularly divided
into segments by the successive accretions of growth ; it is
solid, opaque, and glossy : sculpture, slight concentric lines of
growth, and occasionally a few indistinct and extremely fine
longitudinal stria? towards the narrower end ; these strias, when
they occur, are not very numerous, and are only visible
with the aid of a magnifier: colour ivory-white, with some-
times an ochreous stain on the narrower part, caused by

* Tooth shell.

t Corrupted from Enthalium, an ancient name of the genus.

19.2 DENTALIID.E.

an admixture of mud with the sand in which this species
burrows : margin at the anterior or broader end more or
less jagged, owing to that part of the shell being newly
formed and consequently much thinner than other parts ; at
the posterior or narrower end it is usually truncated in adult
specimens, and furnished with a very short sloping and oblique
pipe or tubular appendage having a pear-shaped orifice ; there
is also occasionally at the point on the convex side a notch or
groove, in a line with the front or smaller part of the tubular
appendage, and this notch is rarely extended into a short and
narrow slit or channel. L. 1*5. B. 0485.

Var. anulata. Narrower and more regularly cylindrical,
ornamented with white ring-like marks of growth.

Habitat : Gregarious in sand, from 3 f. to the
greatest depth explored on our coasts. Captain Beechey
dredged it alive in 145 f. off the Mull of Galloway. It
is much more common in the north than in the south.
The variety occurs in Shetland at a depth of from 85
to 90 f. Its annulated appearance reminds one of the
testaceous sheath in certain species of Teredo. As an
upper tertiary fossil, D. entails is generally diffused both
in time and space, from the glacial " drift " to the red
Crag at home, and from the newer deposits in the
Christiania district, at a height of 100-150 feet above
the sea-level (Sars) to the miocene formation in the
Vienna basin (Homes). Its foreign distribution in a
recent state is also very extensive, although it is pro-
bable that D. Tarentinum has been mistaken for it in
compiling many local lists. Steenstrup collected it in
Iceland; Loven, Sars, and others in Scandinavia (4-200
f.); Mace at Cherbourg; Cailliaud in the Loire-Infe-
rieure; and H. Martin in the Gulf of Lyons; Olivi has
recorded it from the Adriatic, Maravigna and Scacchi
from Naples, Forbes from the iEgean, Mighels from
the State of Maine, and P. Carpenter from North-
west America.

DENTALIUM. 193

This Dentalium, if placed in a vessel of sea-water
without sand, is evidently uneasy : it contrives to jerk
about slowly and clumsily, by attaching the central point
of its foot like the sucker of a leech ; and then, spread-
ing out the side lobes to their full extent triangle-wise 3
it doubles up the foot, and twists itself round with a
sort of napping movement. If placed in a bed of sand^
deep enough to cover the shell at a moderately inclined
angle, the foot becomes conical and elongated, and soon
effects a passage for the whole body, leaving only the
top uncovered, to keep the gills supplied with water
or air. The ' Proceedings of the Zoological Society • for
1864 contain some interesting particulars of the use
and mode of capture in Vancouver's Isle and British
Columbia of D. pretiosum (Nuttall), which appears to be
identical with our species. Mr. Lord says that these
shells were employed as money by the Indians of North-
west America before the introduction, bv the Hudson's
Bay Company, of blankets, which to a great extent
superseded the tooth-shells as a medium of purchase.
u A slave, a canoe, or a squaw, is worth in these days as
many blankets ; but it used to be so many strings of
Dentalia." The value of a Dentalium depends upon its
length. Twenty-five long shells, strung together end to
end, make a fathom, and are called a " Hi- qua/' At one
time such a string would have been worth about £50 ster-
ling. The shells inhabit the soft sand, in the snug bays
and harbours that abound along the west coast of Van-
couver's Island, at a depth of from 3 to 5 f. The habit
of the Dentalium is to bury itself in the sand, one end of
the shell being invariably downwards, and the other end
close to the surface. " This position the wily savage
turns to good account, and has adopted a most ingenious
mode of capturing the much-prized shell. He arms

VOL. III. k

194 DENTALIID.E.

himself with a long spear, the haft made of light deal,
to the end of which is fastened a strip of wood placed
transversely, but driven full of teeth made of bone,
resembling exactly a long comb with the teeth very wide
apart. A squaw sits in the stern of the canoe, and
paddles it slowly along, whilst the Indian with the spear
stands in the bow. He now stabs the comb-like im-
plement into the sand at the bottom of the water, and
after giving two or three such stabs draws it up to look
at it; if he has been successful, perhaps four or five
Dent alia have heen impaled on the teeth of the spear ."
At one period, perhaps a remote one in the history of
the inland tribes of Indians, Dentalia were worn as
ornaments; they are found in old graves, quite 1000
miles from the sea, mixed with stone beads and small
bits of the nacre of Haliotis, of an irregular shape, but
with a small hole drilled through each piece. Rows of
these tooth-shells may be seen in the ethnological cases
at the British Museum. Sometimes the top of the
shell is excavated instead of truncated, and in such case
the pipe does not project beyond the edge. The lip of
the pipe is expanded and reflected in some of my speci-
mens. The fry are very slender, and are marked with
a few slight concentric ribs ; the point forms an oval
bulb, and has a minute circular orifice.

It is the Tubulus antalis of Martini, and D. India-
novum of P. Carpenter. In Gmelin's compilation the
description is made up of this species and D. Taren-
tinum. The same confusion exists in works of the
older writers on European and British shells.

DENTALIUM. 195

2. D. Tarenti'num *, Lamarck.

D. tarentinum. Lam. An. sans Vert. v. p. 345. D. Tarentinum, F. & H.
ii. p. 451, pi. lvii. f. 12.

Body yellowish-white : tentacles very long, ringed like worms,
with sucker- shaped tips : palps usually eight in number, four
on each side of the mouth, but difficult to make out ; they are
of different sizes, and covered with vibratile cilia : foot flanked
on either side by a sinuated symmetrical lobe or flap.

Shell less slender and rather more curved than D. entails,
not so apt to be segmented, very solid and opaque, mostly dull
and lustreless : sculpture, fine and regular longitudinal striae
towards the point; and the entire surface appears, under a good
magnifying power, covered with extremely numerous and de-
licate impressed lines in the same direction ; there are also
the usual marks of growth : colour creamy, with sometimes a
reddish-brown tinge, or clouded rings denoting the periodical
lines of growth, and occasionally a pinkish hue near the point :
margin at the anterior end jagged, as in the other species ; at
the posterior end it is abruptly truncated, and furnished with
a very short and small straight pipe, placed in the middle and
having a circular orifice ; it has no notch, groove, slit, or
channel. L. 1-3. B. 02.

Habitat : From low-water mark at spring tides
(Oxwich Bay, near Swansea, J. G. J.) to 25 f., in the
Channel Isles, Sonth of England, Bristol Channel, Car-
digan Bay (J. G. J.), Bantry Bay (Mrs. Puxley and
J. D. Humphreys), and Arran Isle, co. Galway (Barlee).
At the latter place it was dredged with D. entalis, but
in a larger numerical proportion. Fossil in the Sub-
apennine tertiaries (Brocehi), and Sicily (Philippi, as
D. entalis) . The present species has a southern range
from the north of France to Gibraltar, both sides of the
Mediterranean, and the Adriatic, in 3-40 f. It has
usually been regarded as D. entalis.

* From it* having been found at Tarento, in Italy.

k2

196 dentaliidjE.

The present species does not generally attain the
same size as the last, although I received from Lady
Wilkinson a specimen two inches long and only half-
grown, which she picked up on the sands in Oxwich Bay.
The shell differs from D. entails in being shorter,
broader, thicker, not glossy, and having distinct and regu-
lar striae ; in the posterior end being abruptly cut off, and
the terminal pipe being round with a circular orifice, and
in never having any notch or slit ; it is also sometimes
of a pinkish hue at the point. In the adult the striae
cover the whole surface, and not merely the narrower
part ; in the young these are fine ribs.

Lister first noticed this shell as British, from Barn-
staple Bay. Da Costa described and figured it as D.
vulgare, a name which ought in justice to be preferred,
because that given by Lamarck was not only long sub-
sequent in point of date, but unsupported by a proper
description. He says D. Tarentinum is slender, some-
what curved, and smooth, with a reddish base. How-
ever, I suppose we must accept the proposition made by
the late Mr. G. B. Sowerby in the ( Zoological Journal '
for 1829, and use the latter name as the one best
known to conchologists. It is not the D. dent alls of
Linne, as supposed by Montagu and his followers.
The young is the D. striatum of the last-named author,
although not of his predecessor, Bom. In a worn state
it is Turton's D. labiatum, and D. politum, afterwards
changed to D. laeve.

The collection of Mr. J. D. Humphreys contains a
specimen of D. dentalis, from Bantry, mixed with the last
species. D. dentalis is common on the western shores of
France, from the mouth of the Loire southwards, as well
as in Portugal and Spain, the Mediterranean, Adriatic,
iEgean, Madeira, and Canary Isles. Fossil in the

DEXTALIITM. 197

Red and Coralline Crag (S.Wood). It has nine lon-
gitudinal ribs, besides frequently a stria between each
rib, but no fine impressed lines as in D. Tarentinum ; and
it is more angulated. This may have been the shell
of which Miss Pocock found several specimens " on the
sandy coast of Cornwall, near Lelant, in the year 1802/'
but which Donovan mistook for another species and
named D. octangulatum. Perhaps D. dent alls may
hereafter be discovered on our southern or Irish coasts.
It is the D. novemcostatum of Lamarck, and D. vulgare
of H. and A. Adams.

D. abyssorum of Sars once lived, and possibly sur-
vives, in our northern seas, I dredged two or three
young specimens in Shetland on different occasions;
but they had a semifossilized look. This species in-
habits the western coasts of Sweden and Norway, at
depths varying from 40 to 150 f. Sars has identified it
with D. striolatum of Stimpson from the east coast of
North America ; and it is most likely the D. attenuatum
of Say from Massachusetts. D. abyssorum is one of
our glacial relics ; it occurs in the boulder- clay at Brid-
lington (S. Wood, as " D. entale") and Wick (Peach) ;
Moel Tryfaen (Darbishire) ; Banff (Forbes, as D. den-
talis); Preston (J. Smith, as D. striatum); newer and
older deposits at Chris tiania (Sars), in the former
at 100-120 feet, and in the latter at 460 feet above the
sea-level. It is longer and thinner than D. dent alia,
and has more ribs : it is not so finely striated as D.
Tarentinum, and wants the impressed lines. The ter-
minal process is like that of D. entails.

D. striatum of Born (D. octangulatum, Donovan, D.
octogonum, Lamarck, and D. striatulum, Turton) is a
tropical shell, and has been wrongly considered British
on very suspicious authority. Turton' s collection con-

198 dentaliidjE.

tained specimens ; and I have likewise one which Dr.
Leach sent to Mr. Dillwyn, under the name of D. octo-
hedra, as found in Kent.

D. eburneum, afterwards D. album of Tnrton (D. vari-
abile, Deshayes), is another un-English or spurious
species; its native country is said to be the East Indies.

D. semistriatum of Turton must be, provisionally at
least, placed in the same category, although specimens
were taken by Mr. Humphreys from the stomach of a
red gurnard at Cork. I believe Turton' s specimens
came from the same quarter, notwithstanding that
Dublin Bay is the locality given by him. It may be
the D. semipolitum of Broderip and Sowerby, or D.
semistriolatum of Guilding : if the former, the habitat is
unknown ; if the latter, it is West-Indian.

D. clausum of Turton is certainly not a Dentalium,
nor even a shell ; it seems to be the lower part of the
quill of a sea-bird's wing feather.

The cases of British species of Ditrupa (a genus of
testaceous Annelids) may easily be distinguished from
the shells of any species of Dentalium by their being
constricted near the front, and never having the tubular
appendage at the smaller end. They are thicker, and
of a crystalline structure. Such are Ditrupa arietina,
Miiller (Dentalium subulatum, Deshayes), and Ditrupa
gadus, Montagu (Dentalium coarctatum, Desh.).

GASTEROPODA. 199

Class GASTEROPODA.

(See Vol. I. p. 51.)

In considering the natural distribution of this group, it
will be found that the systems of classification which
have been propounded by naturalists since the post-
Linnean revolution are so numerous, that the student
is apt to be lost in the perplexing labyrinth into which
they lead him. That of the great Cuvier, however,
seems to have stood its ground better than any other,
and is commended by its greater simplicity. It is
founded on differences in the nature and position of the
gills or respiratory organs. Some modification has
been rendered necessary by the investigations of later
physiologists ; and I will submit a scheme, which
appears to me sufficient to classify the Gasteropoda,
without making any pretence to novelty or perfection.
I would adopt the following eight orders.

1. Cyclobranchiata, (Cyclobranches) Cuvier.

Gills arranged in two separate rows, one on each side of
the body, and covered by the mantle. Chitonidce.

2. Pectinibranchiata, (Pectinibranches) Cuvier.

Gills consisting of one or two plumes (usually a single
plume), placed above the head, or on either side of it, and
covered by the mantle. Patellidce, Trochidce, and many other
families, having (invariably in the young state) a spiral or
turbinated shell with an entire mouth.

3. SlPHONOBRANCHIATA, GoldftlSS.

Gills consisting of one or two plumes, placed obliquely on
the anterior part of the back, and contained in a cavity of the
mantle, which is prolonged into a tubular canal. Mv.ricidce,

200 GASTEROPODA.

Cyprceiclce, and other families, having a spiral shell with a
channelled mouth.

4. Pulmonobranchiata, Sowerby.

Respiratory apparatus consisting principally of an internal
cavity or pouch, formed by a fold of the mantle, and lined
with a network of vessels. Limacidce, Helicidce, and other
land and freshwater univalves, besides a few marine kinds,
some of which are naked and others provided with shells.

5. Pleurobranchiata, Gray.

Gills forming a single row, placed on the right side of the
body, and covered by the mantle. Bullulce.

6. Nudibranchiata, [Nudibranches] Cuvier.

• Gills exposed, and forming a tuft on the back. Doridklce
and most Sea- slugs.

7. Pellibranchiata, Alder & Hancock.

Respiratory apparatus consisting of a net-work of vessels
diffused over the outer surface of the mantle. LimapontiidcB,
and small Sea-slugs of an inferior type.

8. Nucleobranchiata, De Blainville.

Respiratory apparatus consisting of symmetrical filaments
associated with the digestive organs in a nucleus placed on
the back. Carinaria and a few other pelagic mollusca of a
peculiar kind (Heteropoda), none of which are British.

In the Prosobranches of Milne-Edwards (which con-
stitute the first three orders) the gills are almost always
enclosed in a vaulted chamber or cavity, which is placed
on the front part of the body; the sexes are separate ; and
the shell is complete in all stages of growth. In his
Opisthobranch.es (which constitute the fifth and sixth
orders) the gills are never enclosed in a special cavity or

GASTEROPODA. 201

receptacle, but are more or less exposed at the back or
sides on the hinder part of the body ; they are herma-
phrodite ; and the shell is completely formed in the fry,
but often disappears in the adult or is incomplete.
According to Lacaze-Duthiers the Gasteropoda are
formed on an unsymmetrical plan ; the organs of diges-
tion are placed on one side, instead of in the middle as
in the Acephala ; and the organs of sense are more deve-
loped, and usually lodged in a head.

Our knowledge of the plan of arrangement, so far as
regards the teeth on the lingual membrane of such
Gasteropoda as possess this curious apparatus, is too
imperfect to make it form part of any scheme of classi-
cation. Loven, Troschel, Gray, and Macdonald have to
a certain extent pursued the subject, and attach much
importance to it. Dr. Gray separated on this ground
his Ctenobranchiata into two suborders — Proboscidifera
and Rostrifera — treating the one as zoophagous, and
the other as phytophagous : but we find in the latter
division Conus, Cypraa, Aporrhais, Fusus, Vermetus,
Ccecanij Capulus, Calyptr&a, and many other genera
which are not vegetable-eaters, Pleurotomatida placed
among the Proboscidifera, and Conidce among the
Rostrifera (both of these families having precisely the
same kind and disposition of teeth) , besides many other
like incongruities. At the same time it is evident that
this spinous organ of deglutition affords a useful cha-
racter to distinguish certain genera and even higher
groups ; and I trust that a further examination of the
subject will enable us to make it available for that pur-
pose.

The embryology, or history of the development of the
Gasteropoda, has been carefully investigated by a host of
able physiologists from the time of Stiebel (1815) to this

K O

202 GASTEROPODA.

day. Grant, Quatrefages, Dumortier, Leuckart, F.
M tiller, Laurent, Sars, Van Beneden, Rathke, Loven,
Milne-Edwards, Nordmann, Kolliker, Gegenbaur,
Krohn, Clarapede, Vogt, and Lacaze-Duthiers are some
of those who have distinguished themselves by such
researches. All their observations show that the Gas-
teropoda pass through a series of metamorphoses before
attaining their perfect state, and that the duration of
the larval state is often considerable, compared with the
whole period of their existence.

Their shells appear to have a more uniform structure
than those of the Acephala. Dr. Carpenter says " There
is not by any means the same amount of diversity in
the structure of the shell in the different subdivisions of
this group as that which we have met with among the
Conchiferous Acephala. There is a certain typical plan
of construction that seems common to by far the greater
number of them ; and any considerable departures from
it are uncommon. The small proportion of animal
matter contained in most of these shells is a very marked
feature in their character, and it serves to render other
features indistinct." A univalve shell consists of three
layers of cellular plates, each of the upper two layers
lying unconformably on the one immediately below it,
and every plate being composed of a single series of
elongated prismatic cells, which cohere lengthwise. He
dissents from the idea of Dr. Gray that the structural
arrangement is the result of crystalline action. The shells
of mollusca were formerly regarded as a mere exuda-
tion of calcareous matter, the particles of which were
held together by a sort of animal glue. Carpenter
is of opinion that the appearance of prismatic crystal-
lization in certain shells is entirely due to the moulding
of the calcareous matter within their cells. He agrees

GHITONIDiE. 203

with Dr. Bowerbank in his account of the composition
of univalve shells, as evincing a definite organic arrange-
ment and not a simple crystallization.

Order I. CYCLOBHANCHIATA.
Family CHITO'NIME, Guilding.

Body oval, oblong, or elongated, semicylindrical, rounded at
each end : mantle thick, covering the back, and encircling the
sides with a girdle which is free at its edges : head sessile,
surmounted by a membranous veil or hood, and containing a
pair of horny jaws and the front of a long and slender tongue
bristling with numerous teeth, which extends into the interior
of the body, and is folded up within it : no tentacles or ei/es :
gills forming a row of small pyramids on each side, which
meet behind the head, lying between the mantle and the foot,
and extending from behind to the front : foot muscular, occu-
pying the whole of the under surface : vent or excretory duct
placed opposite to the head at the end of the foot.

Shell composed of separate arched plates, which are inserted
in the mantle along the back breadthwise ; they are usually
external.

I am not surprised at Lamarck calling this a singular
and strange group, nor that there has been such difficulty
in assigning to it a definite place among the Inverte-
brata. In the larval state they resemble Isopodous
Crustaceans, or they might even be mistaken for tiny
Trilobites ; and the adult may be compared to Onisci de-
prived of antennse, eyes, and feet. They are also not unlike
species of Aphrodita. When a boy I was cruelly deceived
in thinking that I had found a huge and new Chiton,
having got hold of a Sea-mouse in the sand at low water.
De Blainville believed that their natural affinities lie
with the Annelids, and he raised them to a tribal rank
under the name of Polyplaxiphora. The circulatory

204 chitonid^e.

system is complicated; Cuvier ascertained that each
auricle opened into the heart by two distinct orifices, a
disposition of which he had not detected another instance
in the animal kingdom. Milne-Edwards considered
them a satellite group of the Mollusca, fancifully com-
paring the Organization of the Invertebrata to the side-
real system. But the general plan of their structure
is that of the limpet ; the only differences of any import-
ance consist in the latter having tentacles and eyes, which
are wanting in the Chitonidce, and in the shell of the one
being a single piece, while the other is composed of
several pieces which form together an elongated buckler.
In the genus Cylichna we find one species (C. truncata)
with tentacles, and another (C. cylindracea) without ten-
tacles ; and in each of the genera Eulima, Mangelia, and
Amphisphyra, similar discrepancies occur with respect to
the presence or absence of eyes in certain species. The
most obvious distinction between Chiton and Patella con-
sists in the arrangement of the gills and the multivalve or
univalve character of the shell. It seems sufficient to
group them in two families, separate but not widely
apart. Adanson and Strom pointed out the affinity of
Chiton to Patella ; and Poli showed that their spinous
tongues were exactly similar. The Rev. Lansdown
Guilding, in a valuable monograph of the present family
(Zool. Journ. 1830), called this apparatus "trachy-
derma/'

Genus CHITON*, Linne. PI. V. f. 2.

Body oval or oblong : girdle scaly, bristly, tufted, or mem-
branous, and fringed with short spines.

Shell usually boat-like, composed of eight plates, which are

* Coat of mail.

CHITON. 205

external and overlap one another in an imbricated or tile-like
fashion ; the last or hindmost plate has a small overhanging
boss in the middle.

These " punaises de mer," as Vallisnieri calls them —
Petiver has a prettier name, " Oscabrions " — move very
slowly, creeping or rather gliding, onwards, backwards,
or sideways, with an imperceptible and stealthy pace.
Mr. Guilding says of the West-Indian kinds (and his re-
marks will in most particulars apply to the British spe-
cies) , "They seem to feed entirely by night. Though they
remain stationary during the day, when disturbed they
will often creep away with a slow and equal pace, often
sliding sideways, and creeping under the rocks and stones
for concealment. If accidentally reversed, they soon re-
cover their position by violently contorting and undula-
ting the zone ; and for defence they sometimes (when de-
tached) roll themselves up like wood-lice. Some of the
larger kinds, especially of Ac anthopleur a, are eagerly de-
voured by the lower orders in the West Indies, who
have the folly to call them { beef ; ' the thick fleshy
foot is cut away from the living animal and swallowed
raw, while the viscera are rejected. We have here a
large pale Chiton, which is said to be poisonous." Ladies
who are not good sailors, and are fond of trying new
preventives against sea-sickness, may (if they can) swal-
low raw Chitons, and so imitate the Iceland fishermen,
who pretend that the " hav-bceggeluus " (sea-bugs) are
an effectual remedy against this malady, and also that
they quench thirst. One kind is easily procured at low
water on most of our beaches by turning over loose
stones. Such an occupation just before encountering a
voyage might beguile the tedious interval — or perchance
the deglutition of these strange boluses might by anti-
cipating the evil rob the passage of its horrors.

206 CHITONID^.

Poli called the animal Lophyrus, and he has given some
particulars of its anatomy. Neither Cuvier nor Leach
found any male organ in the individuals they examined ;
and little seems to be known of their sexual relations.
Their embryogeny, however, is no longer a mystery. In
the ( Transactions of the Royal Academy of Sciences at
Stockholm/ for 1855 will be found a most interesting ac-
count by Professor Loven of his observations on the de-
velopment of C. marginatus. He says that some indivi-
duals, kept in confinement, laid their eggs, loosely united
in clusters of from 7 to 16, upon small stones. Each e^
has a thick envelope. The embryo, which is exactly of
an oval shape, and without any trace of shell, is divided
by a circular indentation into two nearly equal parts.
The upper half is fringed with cirri, by means of which
the embryo swims ; and each side of the line of inden-
tation is furnished with a tuft of very fine filaments.
Close to this line on either side are perceptible two dark
points, which are the eyes. "When freed from the egg }
the embryo assumes a more lengthened shape ; the lower
half soon afterwards exhibits transverse furrows and
joints, of which seven (besides the front lobe) are dis-
tinguishable ; and some granulations now make their
appearance as the first rudiments of the shell. The
animal bends itself frequently ; it is still quite soft, and
can only swim. Subsequently it begins to crawl. The
eyes are then more conspicuous; the joints become
separated, and acquire a shelly consistence; the cirri
and tufts disappear; and the head is perfectly formed
with its membranous hood. The embryo at this stage
sometimes swims and sometimes crawls. The eyes are
placed on distinct protuberances, and consist of pigment-
spots and lenses ; and the foot is rather enlarged,
although some time elapses before this part attains its

CHITON. 207

full size in proportion to the head. Loven justly re-
marks that, if we compare the development of Chiton
with that of other Mollusca, it is evident that the circle
of cirri, bv means of which the animal moves in its first
or swimming stage, corresponds with the cirri of the
front lobe in the young of other Gasteropoda and of the
Acephala. Mr. Clark recorded some important remarks
on the reproduction of C. marginatus in the f Annals
and Magazine of Natural History' for December 1855,
being the same year as that in which LoveVs were pub-
lished. One of several individuals, placed in a vessel
of sea- water on the 23rd July 1855, poured out for
several minutes a continuous stream of flaky-white vis-
cous matter, like a fleecy cloud, and then discharged
ova — not in volleys, but one or two at every second for at
least fifteen minutes, forming a batch of from 1300 to
1500 ; a thousand or more remained in the ovary, per-
haps not sufficiently matured for parturition. The fluid
and ova were emitted " from under the centre of
the coriaceous integument of the posterior terminal
valve/' in the same way as the author had described it
to take place from the posterior extremity of Denta-
lium. Each egg was enveloped in a pale yellow mem-
brane, and was of a somewhat globular shape, being a
little compressed or oblate at what may be termed the
axis; it appeared to be about the 100th of an inch in
diameter. The ova were entangled in the tenacious
fluid which had been previously poured out — this being
seemingly a provision for preventing their being washed
away until the fry were prepared to emerge. In about
24 hours afterwards the fry became disengaged from
their common nidus, and swam about with great viva-
city in every direction, crossing a large breakfast saucer
in 30 or 40 seconds. They had by that time lost the

208 CHITONIDiE.

subglobular figure, and taken that of a subelongated
oval, approaching the shape of an adult Chiton. When
the swimming-action commenced, only half the animal
was liberated from the capsule or membranous integu-
ment, the other half being still enclosed, with the empty
portion of the capsule folded over it. With a power of
300 linear Mr. Clark saw the elements of the four an-
terior valves, as well as the buccal depression and head ;
at this stage of development he could not perceive any
metamorphosis. In the course of the next five days
the animal had altogether cast off the embrvonic cover-
ing, when it exhibited the complete form of a Chiton,
and adhered to the bottom of the vessel. He apparently
did not at any period detect the eyes w-hich Loven had
noticed. Mr. Clark further remarked that the fry
during its phase of rapid movement often rolled itself
into a ball. The slight discrepancy between these ob-
servations of the Swedish, and English naturalists may
be accounted for bv those of the former being more
complete, and perhaps having been made under more
favourable circumstances. Twenty years ago Milne-
Edwards published, in conjunction with Quatrefages
and Blanchard, the result of anatomical and zoological
researches made on the shores of Sicily and France.
Chiton was one of the subjects of their investigation ;
but I am not aware that any details were given. Milne-
Edwards was induced, however, by these researches to
declare that he had arrived at a different conclusion
from that which w 7 as hazarded in the ' Vestiges of Crea-
tion/ viz. that the embryo of the higher animals, in-
cluding man himself, presented in succession modes of
organization analogous to the permanent state of the
principal lower types of the animal kingdom. On the
contrary, he was of opinion that the embryos of the Mol-

CHITON. 209

lusca and the Mammalia had their own respective modes
of organization, and that the theory above mentioned was
by no means justified by the facts. Each plate of a Chiton
has its sides diagonally parted, and is divided into three
triangular areas. The base of the central area is covered
by the edges of the preceding plate, and the base of each
lateral area is inserted in the girdle or marginal band of
the mantle. The front plate, being that which protects
the head, is semicircular ; the hindmost plate is oval,
and is furnished with a boss or point, which overhangs
the rear and corresponds with the apex of the cone in the
shell of Patella. In many species the plates are inserted
more firmly in the girdle by means of marginal notches.
These were first noticed by Fabricius in his description
of C. marmoreus. They vary in number and fineness
according to the species. The spines and valves which
cover the girdle in most species are calcareous. The
structure of the shell agrees with that of Patella,
although the details are somewhat different. Carpenter
says, C( The external layer, which is usually impregnated
by colouring matter, does not exhibit the laminations
which are seen in Patella, but in their stead presents
everywhere a delicate fibrous structure, the fibres being
arranged parallel to the surface. The superficial part of
this layer is perforated by large canals, which pass down
obliquely into its substance, without penetrating so far
as the middle layer. The purpose of these canals, which
remind us of the perforations of Terebratula, is by no
means apparent. In the deeper part of this coloured
external layer, which is of great toughness, there is a
layer of minute cells which seem to lie between the
fibres; and below this, again, is a layer entirely com-
posed of large flat pavement-like cells, as in Patella.
The internal layer seems to have the same nearly homo-

210 chitonid,e.

geneous texture as the external." The tubular structure
of the outer layer appears to be accompanied by the ab-
sence of an epidermis, respecting which I offered an
explanation in my account of the Brachiopoda at p. 6
of Vol. II. The second volume of the ' Zoological Jour-
nal ■ (1825) contains an accurate description, by the
Rev. R. T. Lowe, of some Scotch Chitons-, and Baron
Middendorff has given an elaborate essay on the Russian
kinds, with details of their anatomy. The genus abounds
in species, which are all more or less gregarious. Reeve
has lately enumerated 189, and this list is not complete.
The British Chitons live attached to rocks, stones, and
old shells ; they inhabit various depths of water, and
many live between tide-marks. Some of their shelly
plates occur in upper tertiary strata ; others of extinct
form have been found in older and even ancient forma-
tions. Gray has made twenty genera out of the one so
familiar to us by name. I do not consider it necessary
to apply this rate of multiplication to our native species :
the following conspectus may suffice to distinguish
them : —

A. Girdle covered with spines, and having also tufts of bristles.

(Acanthochites, Leach, Jide Risso.) 1. C. fascicularis.

2. C. discrepans.

B. Girdle spinous, without tufts. (Acanthopleura, Guilding).

3. C. Hanleyi.

C. Girdle covered with scales or granules. (Lepidopleurus,

Leach, fide Risso.) 4. C. cancellatus. 5. C. albus.
6. C. cinereus. 7. 0. marginatus. 8. C. ruber.

D. Girdle apparently reticulated. 9. C. l&vis.

E. Girdle membranous. 10. C. marmoreus.

CHITON. 211

1. Chiton fas'cicula'ris*, Linne.
C. fascicular^, Linn. S. N. p. 1106 ; F. & H. ii. p. 393, pi. lix. f. 5.

Body oblong, yellowish with often a tinge of brown : man-
tle fleshy, bordered by a narrow hem of a paler and almost
transparent hue : girdle moderately broad, more or less closely
covered with short spines, which are usually tawny or greyish ;
besides this armature there is a thick tuft of 14 longer spines, or
rather bristles, of a paler or whitish colour (occasionally green-
ish or golden), between each plate of the shell at the point
of junction on both sides, and 4 more, close to the front
or head-plate, making in all 18 ; margin fringed with
spines of an intermediate length, and finely ciliated at its outer
edges : head representing an arc of |rds of a circle : mouth
large, of a purplish colour, and star-shaped, being divided into
a dozen lobes, each of which radiates from the centre and is
defined by a black line : gills visible throughout, larger towards
the tail, and diminishing in size towards the head : foot oblong,
of an orange tint, broader in front, and bluntly pointed behind,
thicker towards the sides than in the middle of the sole : vent
conical and short, projecting above the tail or hinder extremity
of the foot, and placed in a channel or notch.

Shell formed of the usual number of plates, which are
shield-like and somewhat compressed, solid, opaque, and of
rather a dull hue ; they occupy |-ths of the entire breadth ;
when separated, the notch in front of each is very large and
deep, and is flanked on either side by a broad shoulder : sculp-
ture, rather fine but not very numerous oval granules, like
those of shagreen, on each side of a broadish central ridge or
keel, which extends along the back ; they are arranged length-
wise in lines converging towards the beak or point of the
ridge ; their tops are flattened and sometimes slightly concave ;
the central or dorsal ridge is closely striated longitudinally or
divided by lines, and sometimes punctured, exposing the tu-
bular structure ; it has usually a rubbed and somewhat po-
lished appearance : colour brown, chocolate, orange, yellow,
pinkish, or red, now and then mottled or streaked with
white, pale green, or brown : beaks small and rather promi-

* Covered with small bundles or tufts.

212 CHITONID^.

nent : inside smooth and polished, of a greenish cast : notches
slight, 5 on the head-plate, 1 on each side of every middle
plate, and 2 on the tail-plate, making altogether 19. L. 0-75.

B. 0-375.

Yar. 1. attenuata. Much longer and narrower in proportion
to the breadth.

Yar. 2. gracilis. Longer than usual, with finer sculpture :
oirdle broader and membranous, sparsely set with spines, and
mostly having an extra tuft (occasionally two) at the tail.

C. gracilis, Jeffreys, in Ann. Nat. Hist. Feb. 1859, p. 106.

Habitat : Rocks, stones, and oyster- shells, on every
part of our coast from low-water mark to 25 f. ; off Mull
of Galloway in 145 f., as C. discrepans (Beecliey) . Var.
1. Oban (Barlee). Var. 2. Weymouth (Metcalfe and
Damon) ; Lul worth (J. G. J.) ; Gronville Bay, Jersey,
with C. discrepans (Norman); Milford Haven (M c An-
drew and Jordan) ; Lough Strangford (Adair) . A speci-
men from the last mentioned locality measures nearly an
inch and a half in length, while the largest that I have of
the typical form (from Unst) is scarcely an inch long.
Fossil in the Coralline Crag, Sutton (S. Wood) ; South
Italian tertiarie s (Philippi) . The foreign distribution of
this species extends from Finmark (Sars) to the iEgean
(Forbes), Barbary (Brander, fide Linne), Morocco
(M f Andrew), Algeria (Weinkauff), and Canary Isles
(M f Andrew), at depths ranging to 20 f. ; but some of
the southern localities which have been published pro-
bably belong to C. discrepans. Malm found it attached
to Laminaria saccharina on the coast of Bohuslan at a
depth of 12 f. The variety gracilis occurs at Etretat, in
Normandy (J. G. J.), and in the Loire-Inferieure
(Cailliaud).

This handsome species crawls backwards as well as
forwards. Mr. Jordan remarks that it appears much

CHITON. 213

more sensible of cold than the Littorina, and that even
about the middle of November it was difficult for him
to find two or three specimens in an hour's search at
Tenby, in a spot where he could during the month of
August get more than as many dozen in the same time.
The fleshy part of the girdle must be porous or vascular,
because it becomes swollen and puffed up if confined
by a ligature ; it is often raised in folds or puckered, to
admit water to the gills. The dorsal ridge is formed
by the wearing away of the granulated surface, showing
that this part of the shell is never renewed. The plates
are frequently encrusted by small spiral Serpula and
Foraminifera, In young shells the triangular compart-
ments are to be seen, as in other species of Chiton.

It may be the u Kalison " of Adanson. The short
description by Linne of C. fascicularis, and the
habitat (Barbary), are rather more applicable to C.
discrepans than to the present species. Writers on the
[Mediterranean shells have evidently mistaken one for
the other. Pennant says his C. crinitus has only seven
valves; but his figure shows eight and the usual number
of tufts. I am also disposed to refer to C. fascicularis
the Acanthochites ceneus of Kisso, and certainly the
AcanthocJuetes vulgaris of Leach. I cannot maintain
the distinction which at first seemed to exist between
the typical form and the variety gracilis, and which in-
duced me to describe the latter as a separate species.
Both have every character in common, except the ad-
ditional tuft ; and that is not constant.

214 chitonid,e.

2. C. dis'crepans *, Brown.

C. discrepans, Brown, 111. Conch, p. 65, pi. xxi. f. 20 ; F. & H. ii. p. 396,
pi. lviii. f. 4.

Body oblong : girdle broad, covered with a thick pile, like
velvet, which is usually of a greyish tint ; tufts similar in
number and arrangement to those of Q. fasciculaHs, but not
so large ; they are whitish or tawny, with sometimes a
greenish hue ; spines of marginal fringe not longer than those
which form the pile.

Shell more convex in the middle than the last species,
occupying only one-half of the entire breadth : plates similar
in shape : sculpture, very fine and numerous round granules,
arranged in rows which converge in a curved direction towards
the beak in each plate ; their tips are flattened in adult speci-
mens, but seldom concave ; ridge prominent and rather sharp,
separated from the granulated portion on each side of it y
closely striated or lineated lengthwise, and having a rubbed
or polished appearance : colour greyish, mottled with dull
reddish-brown ; the ridge is generally darker and sometimes
marked by a black cuneiform streak : beaks sharp and pro-
jecting : inside smooth and polished, of a greenish cast :
notches as in C. fascieularis, but sharper. L. 1-25. B. 0*6.

Habitat : Not uncommon on rocks and stones in the
Channel Isles, from low-water mark to 25 f.; sometimes
associated with C. fascieularis, which is much less fre-
quently met with in this outlying part of Great Britain.
The only other British locality that I am aware of is
Coomb, in Lantivet Bay, Cornwall, as C. crinitus
(Couch) : I have not seen the specimens. It occurs on
the coast of France from the Boulonnais to Nice;
Corsica (Payraudeau) ; Sicily, as C. fascieularis, var.
major (Philippi) ; Balearic Isles and Mogador (M' An-
drew) ; and Loven has enumerated it among the Scan-
dinavian mollusca as C. crinitus (" Boh-Norv. v ) ; but
I fear he mistook a variety of C. fascieularis for the
present species.

* Different, i.e., from C. fascieularis.

CHITON. 215

Mr. Dermis, as well as Mr. Jordan, observed that
specimens found between tide-marks in Herm and
Jersey were very much finer than those dredged
in deep water off the last-mentioned island. This
species differs from C. fascicularis in being larger,
and usually longer in proportion to the breadth ; the
central ridge is more prominent ; the granules are much
smaller and more numerous, and they are invariably
round instead of oval ; the girdle is broader, and clothed
with a thick pile ; the tufts are not so large or con-
spicuous ; and the notches are deeper. The young have
a remarkably elongated shape.

The locality (Tenby) assigned by Brown to C. dis-
crepans belongs to C. fascicularis ; but his statement
that the " papillae" are round can only apply to the
former species. Sowerby considered it (but erroneously)
the C. crinitus of Pennant, which is nothing more than
C. fascicularis. I believe Acanthochites communis and
A. carinatus of Risso may be referred to C. discrepans.

3. C. Hanle'yi*, Bean.

C. Hanleyi (Bean), Suppl. Thorpe's Brit. Mar. Conch, p. 263 ; F. &. H.
ii. p. 398, pi. lxii. f. 2.

Body oblong: girdle rather narrow, tough, covered with
numerous short whitish spines ; those at the posterior side of
each plate, issuing from the corner where it overlaps the next
plate, are a little longer than the rest, and assume a some-
what tufted form.

Shell convex : plates shield-like, with a wide and deep
notch in front, moderately solid and opaque, not glossy : sculp-
ture, numerous but not crowded bead-like tubercles, arranged
in longitudinal rows, which appear in some specimens chain-
like ; these tubercles are smaller, finer, and closer on the crest
or back of each plate, and become coarser and irregular at the

* Named in honour of Mr. Silvanus Hanley, one of the authors of
' British Mollusca ' and other works on conchology.

216 CHITONID^E.

sides ; there is no distinct ridge : colour dirty brown or ashy :
beaks small and moderately pointed : inside porcellanons ; the
margin has no notches, but is indistinctly and microscopically
crenulated. L. 0*4. B. 0-2.

Habitat : Stones and old shells, from 20 to 80 f., in
the following localities : — Plymouth, in trawl refuse, with
Odostomia truncatula and other south of England shells
(Jordan) ; Scarborough (Bean) ; Cullercoats (Alder) ;
Co. Galway (Barlee) ; Co. Antrim (J. G. J.) ; Oban'and
Hebrides (Barlee, M f Andrew, and J. G. J.) ; Moray
Firth (Gordon) ; Shetland (Barlee and J. G. J.) : it is
not common. Coralline Crag, Sutton (S. Wood). It
inhabits every part of the Scandinavian coast, from the
south of Sweden to Finmark, at depths varying from
35 to 120 f. ; Malm noticed it on Lophelia (Oculina)
prolifera. T dredged in the Gulf of Spezzia a young
shell which I considered to be the present species ; and
M. Petit states that Mr. Shuttleworth found two speci-
mens on a Car dium peculiar to- the Caribbean Sea, which
he received among some West-Indian shells. These
southern localities, however, want confirmation.

The lingual membrane is armed with numerous teeth
arranged in rows, two of which are more prominent than
the rest and are furnished with black hooks. Specimens
from the North Sea attain a considerable size. I have
one from Shetland fully three-quarters of an inch long,
and a plate which must have belonged to a specimen
twice that size.

It is the C. strigillatus of S. Wood. The C. Nag elf ar
of Loven is C. Hanleyi of an extraordinary large size ;
and so is the C. abyssorum of Sars.

CHITON. 21

4. C. cancella'tus * (Leach?), G. B. Sowerby, Jun.

C. canccllahts, Sow. Deser. Cat. Brit. Chit. p. 4, f. 104, 104 a. b, and 105 ;
F. & H. ii. p. 410, pi. lix. f. 3.

Body oblong : girdle narrow, irregularly coated with small
rather shiny yellowish- white granules; margin closely fringed
with short spines.

Shell semicylindrical, very convex : plates transversely ob-
long and narrow, moderately solid and opaque, and slightly
glossy ; each of the middle plates is divided into three distinct
compartments (as described in the account of the genus), the
lateral compartments in this species being elevated consider-
ably above the middle portion, but together scarcely equalling
it in superficial area : sculpture, extremely minute round,
compressed, and close-set granules, arranged in numerous
chain-like rows, which are longitudinal on the first and last
plates and on the middle compartment of the other six, and
converge to the centre or apex of the triangle in the side com-
partments, so as to present a somewhat divaricating appear-
ance ; there is no central ridge : colour yellowish-white : beaks
inconspicuous, except on the tail-plate : inside glossy, exhibit-
ing some of the chain-like sculpture, beside sharp semicircular
leaves at each side of all but the head-plate, which form the
shoulders of those plates ; margin not notched, but indis-
tinctly and microscopically crenulated. L. 0*225. B. 0-125.

Habitat : Stones, old shells, and occasionally Ulva?
and small sea-weeds in the laminarian zone, Channel
Isles, south of England, Isle of Man, north and west of
Ireland, Hebrides, and Shetland, at depths between 5 and
40 f. ; it is rather local, but not uncommon. Its foreign
distribution is wide, and embraces the Norwegian and
Swedish coasts from 50 to 150 f., and those of France
from E tret at to the Gulf of Lvons.

Malm found it on Lophelia prolifera. The links of
the chain-like rows of granules on this small and pretty

* Latticed.
VOL. III. L

218 CHITONID/E.

species resemble punctures, and produce a latticed ap-
pearance.

It is the C. albus of Pulteney and Montagu (but not

of Linne), C. alveolus of Sars, and probably C. tuber cu-

latus of Leach's l Mollusca of Great Britain/

5. C. cine'reus"*, Linne.

C. cinerea, Linn. S. N. p. 1107. C. asettus, F. & H. ii. p. 407, pi. lix.
f. 1, 2, and (animal) pi. A A. f. 5.

Body broadly oval, brownish-yellow, orange, or of a some-
what tawny fleshcolour : mantle thin : girdle rather narrow,
covered with small oval, rather shiny, yellowish-white or
darker-colonred granules, which lie one upon another in a thick
heap ; margin closely fringed with sharp whitish spines : head
semicircular, surrounded by a narrow hood : mouth forming
when at rest a transverse and concentrically wrinkled slit ; but
when open and showing the teeth, it becomes circular : gills
pale brownish-yellow ; only from 6 to 10 of the plumes or
leaflets nearest the tail, on either side are visible, the others
being convoluted and withdrawn : foot oval, broader in front,
and margined by a pinkish line : vent short and tubular.

Shell compressed : plates as in C. cancellatus, but less solid
in proportion to the size ; lateral compartments indistinct :
sculpture similar to that of the last species, although much
finer and never exhibiting a punctured or cancellated appear-
ance : ridge slight, more or less conspicuous : colour pale yel-
lowish, often irregularly streaked lengthwise with dark lines,
and sometimes having a transverse mark of the same hue on
the lateral compartment near the beak in each plate : beahs
small: inside porcellanous, streaked in the middle like the
outside, displaying the leaf-like shoulders described in C. can-
cellatus ; margin not notched, but crenulated in the same way
as in the last two species. L. 0-5. B. 0*35.

Var. Hissoi. Shell of a uniform pale yellowish colour.
C. Hissoi, Payraudeau, Moll. Cors. p. 87, pi. iii. f. 3, 4.

Habitat : Stones, and old shells (especially oysters) ,
everywhere in the laminarian, coralline, and deep-sea

* Ash-coloured.

CHITON. 219

zones ; occasionally between tide -marks at high springs ;
off Mull of Galloway, 145 f. (Beechey). Macgillivray
savs he found it at Aberdeen on a starfish ! The
variety is from the west of Scotland in deep water.
"Glacial" bed at Fort William (J. G. J.); Coralline
Crag, Sutton (S. Wood). Greenland (Fabricius and
Eschricht) ; Iceland (Steenstrup and Torell) ; Scandi-
navia, 1-130 f. (Miiller and others) ; north of France
(De Gerville) ; Vigo Bay (M f Andrew) ; and along the
coasts of the Mediterranean to the iEgean, 5-10 f.
(Forbes, as C. Rissoi).

Chemnitz called the specimens in Spengler's cabinet
" the negress/' owing to their swarthy complexion.
When this Chiton opens its mouth and shows its teeth,
a double row of black glistening points, separated by a
central column, is suddenly unfolded, and as rapidly
withdrawn ; this operation is repeated several times in
the course of a minute. Is it caused by the blind
cravings of hunger, or is it a process like that of rumi-
nation, or merely for the purpose of keeping the teeth
clean ? Mr. Dennis says that all the specimens which
he dredged in 17 f., seven or eight miles off Blatching-
ton, on the Sussex coast, are small and light-coloured in
comparison with those procured by him at low water.
The largest specimen I have came from Oban, and
measures T 8 oths of an inch in length by \ an inch in
breadth ; the smallest is not much more than ^oth of an
inch long. The fry are broader than the adult, and their
granules are tubercular, few in number, and apparently
analogous to the external bulbs of the tubular perfora-
tions in shells of Brachiopoda. C. cinereus may be dis-
tinguished from C. cancellatus by its larger size, ex-
panded and compressed shape, finer sculpture, the lateral
compartments being inconspicuous, and by its central

l2

220 chitonidjE.

ridge, beaks, and thicker coating of grannies on the
girdle, which is broader than in that species.

It is the C. asellus in Spengler's monograph of the
genus (Skr. Nat. Selsk. 1797), C.iskindicus of Gmelin
(from Schroter's 'Einleitung } ) , C. fuscatus of Leach (but
not of Brown) , and C. Scoticus of the same author ; the
variety is C. onyx of Spengler.

6. C. ALBUs % Lmne.

C. albus, Linn. S. N. p. 1107 ; F. & H. ii. p. 405, pi. kii. f. 2.

Body narrowly oval, brownish yellow : girdle rather broad,
regularly and closely beaded with glittering equal-sized oval
granules, which have their smaller points towards the beaks
of the shell ; margin fringed with short spines.

Shell rather convex : plates narrowish, solid and opaque,
somewhat glossy ; lateral compartments slightly raised : sculp-
ture, numerous and small granules, arranged in irregular and
wavy lines which converge towards the beaks ; there are also
in adult specimens a few darker marks of growth in each
plate : ridge sharp and conspicuous : colour yellowish-white :
beaks small, prominent : inside porcellanous, with sometimes
a bluish tinge, displaying broad leaf-like shoulders on all the
plates except that which covers the head : notches slight but
distinct, 13 on the head-plate, 11 on the tail-plate, and 2 on
each of the other plates (one on either side), making altogether
36. L. 0-35. B. 0-2.

Habitat : Stones, old shells, and sea- weeds, from
low-water mark to 30 f.; Ballaugh, Isle of Man (Forbes,
from whom I received a specimen in 1841, with a note
of this locality, and named "Chiton, new sp."); west
coast of Scotland (R. T. Lowe and others) ; Burghead,
Moray Firth (Murray, fide Gordon); Buchan, Aberdeen-
shire (Dawson); Wick (Peach); Orkneys (Thomas);
Lerwick and other parts of Shetland (J. G. J.): it is a

* White.

CHITON. 221

local species. Fossil at Fort William (J. G. J.). Its
foreign distribution is entirely northern, viz. Spitz-
bergen, Greenland, Iceland, the Faroe Isles, Norway,
Sweden, and Denmark, in 10-150 f. (Torell, Konig, and
others) ; the coast of Russian Lapland, on the White
Sea (Middendorff) ; Massachusetts (Gould) ; New Eng-
land (Stimpson) ; and State of Maine, in the stomachs
of fishes caught in Casco Bay (Mighels) .

This approaches C. cinereus nearer than any other
species : but it is narrower and higher, and of a uniform
yellowish-white colour ; it has a rather prominent ridge
and beaks ; the sculpture is finer, and not chain-like, but
irregularly disposed in a radiating and wavy manner;
its margin is notched ; and the granulation of the girdle
resembles bead-work. Spiral Foraminifera (Discorbina
rosacea and Truncatulina lobatula) seem fond of attach-
ing themselves to the girdle. The fry have dispro-
portionately large beaks. My finest specimen is from
Scalloway, and measures j^ths of an inch in length, and
half as much in breadth.

It is the C. oryza of Spengler, C. aselloides of Lowe,
and C. sagrinatus of Couthouy.

7. C. margina'tus * 3 Pennant.

C. marginatum. Penn. Brit. Zool. iv. p. 71, tab. xxxvi. f. 2. C. cinereus,
F. & H. ii. p. 402, pi. lviii. f. 1 (as C. marginatum).

Body oval, pale fleshcolour : mantle thin, edged with a
narrow border of light brown : girdle of moderate breadth,
usually puckered on the inner side (owing to the contraction
of the mantle), covered with minute close-set roundish
granules, which lie evenly on the surface ; it is of different
colours, and often variegated by alternate patches of reddish-
brown and yellow ; margin thickly fringed with short but con-
spicuous spines of a yellowish tint : head thick, transversely
oval : mouth round and plaited : gills from 15 to 20 on each
side, triangular, apparently not continued behind the head :

* Bordered.

222 chitonid^:.

foot lanceolate, truncated in front, and broader towards the
tail, which is bluntly pointed.

Shell somewhat convex: plates broad, rather solid and
opaque, without lustre ; lateral compartments scarcely (if at all)
raised, but marked by a slight ridge which extends on each
side from the beak to the front corner : sculpture like shagreen,
composed of not very small oval flattened granules, which are
arranged in two indistinct sets of rows, one length-wise on the
middle compartment, and the other nearly at a right angle on
the lateral compartments from each side to the beak : ridge
distinct and prominent: colour various, forming different
combinations of yellow, reddish-brown, and green, often mot-
tled, or the plates are party-coloured, seldom of the same
hue throughout : beaks strong, prominent, and conspicuous :
inside porcellanous, with frequently a greenish tinge in the
middle, displaying broad leaf-like shoulders on all the plates
except that which covers the head ; the terminal plates often
exhibit white lines which radiate outwards, and represent so
many segments : notches deep, 8 on the head-plate, 10 on the
tail-plate, and 2 on each of the other plates, making altogether
30, besides occasionally an intermediate and slighter notch.
L. 0-6. B. 0-4.

Habitat : Under stones below high water of neap tides
on all our coasts ; common. It is diffused everywhere
throughout the North Atlantic from Faroe (Landt) and
the Loffoden Isles (Sars) to Mogador (M* Andrew) . In
the North Sea it seems to frequent deeper water ; Asb-
jornsen and other writers on the Scandinavian Mollusca
give depths varying from 2 to 40 f. According to Gould,
a single specimen was found on the coast of Massa-
chusetts ; and the C. dentiens of that author, from
Vancouver's Island, appears to be undistinguishable
from our shell.

This Chiton uses the under side of the head, as
well as the foot, in crawling. From one specimen that
I was observing on the 3rd of June 1864, a thin
stream of milky fluid issued, immediately beneath the
anal tube, at short intervals for about two minutes ; the

CHITON. 223

discharge was so copious that the water in the vessel
became turbid. This was probably a seminal secretion.
The colour of the shell is extremely variable. Out of
more than five hundred specimens Bouchard-Chan-
tereaux was unable to find two marked exactly in the
same way. He describes the tongue as horny, bristling
with six longitudinal rows of small tricuspid teeth, those
of the two central rows being blackish and much
stronger than the others. C. marginatus differs from
C. cinereus in being usually of a larger size, narrower,
and more convex or arched; the plates are broader;
the colour is variegated, not streaked ; the sculpture is
much coarser, and not chain-like; the granulation of
the girdle is finer, more minute, and even ; the marginal
spines are stronger and more conspicuous; and the
edges of the plates are deeply notched, instead of being
slightly and indistinctly crenulated. The habitat of the
two species is also different ; this is littoral, while the
other prefers deeper water. In the fry of the present
species the front of each plate is curved.

Two specimens of C. marginatus in Turton's collection,
affixed to separate cards, are named in the Doctor's
handwriting " Chiton ruber" " ; one from u Dublin Bay/'
and the other from a Portmarnock." They correspond
with his description of C. punctatus. Both have been
painted red ! A daughter of Dr. Turton told me that
when her father went out shell-hunting, some young
ladies would occasionally go before him on the beach,
and drop here and there shells which they had taken
with them, in order to play him a merry trick. Let us
suppose that these were the artists who so ingeniously
beautified the specimens above noticed, finding such
perhaps an easy feat compared with that which Shen-
stone's Laura could not accomplish —

" With fresh vermilion paint the rose."

224 CHITONID.E.

A specimen was described by Captain Brown as having
only five plates, nnder the name of C. quinquevalvis.
Other synonyms of the ordinary form appear to be
C. cimex, Chemnitz, C. cimicinus, Landt, C. cinereus,
Laskey and Lowe (bnt not of Linne), C. fuscatus, Brown
and Macgillivray, C. variegatus, Leach (but not of Phi -
lippi), and Lepidopleurus carinatus of the same author.
It may be partly the C. punctatus of Linne.

8. C. ruber"* (Linne), Lowe.

C. richer, Lowe, in Zool. Journ. ii. p. 101, pi. v. f. 2 ; F. & H. ii. p. 309,
pi. lix. f. G, and (animal) pi. A A. f. 6.

Body oval, inclining to oblong, yellow or creanicolour, and ap-
parently of a granular texture: mantle thin : girdle rather broad,
of a mealy aspect, covered with numerous minute spherical
granules which lie evenly on the surface, as in C. marginatum ;
it is chequered with alternate patches of red and white ; margin
thickly fringed with very short spines of the same colour as
the patch to which they belong : head semioval, edged with a
narrow band of brown, which is surmounted by a line of
darker hue : mouth when closed forming an arched slit, also
surrounded by a darker line, and concentrically wrinkled :
gills more exposed than in C. cinereus : foot elliptical, bordered
by a light-brown band, which is much narrower than the one
round the head, and likewise surmounted by a dark line :
vent or excretal duct broad and wedge-shaped.

Shell convex : plates broad, solid, opaque, and glossy ;
lateral compartments indistinct : sculpture, parallel lines of
growth, which are sometimes remarkably strong and con-
spicuous ; with a lens of moderate power it appears otherwise
to be quite smooth ; but if a Coddington or Stanhope be used,
the whole surface is found to be very finely and closely reticu-
lated : ridge more or less prominent, but seldom distinct :
colour reddish-brown of different shades, mottled or streaked
with white or pale yellow: beaks strong and projecting : inside
rosecolour in the middle of each plate, with a greenish hue
on the edges and sides, shouldered as in the foregoing species :

* Ked.

CHITON. 225

notches deep, 9 on the head-plate, 8 on the tail-plate, and 2
on each of the other plates, making altogether 29. L. 0*5.
B. 0-275.

Yar. oblonga. Larger, longer, and more arched. L. 0*65,
B. 0-35.

Habitat : On rocks, stones, old shells, and the
" roots " of Laminaria saccharina, between low-water
mark and 20 f., from South Devon to Shetland ; it is
common in the Avest of Scotland and Lerwick Sound,
where also the variety occurs. Fossil at Fort William
(J. G. J.) . The only southern locality that I can find
recorded is the Adriatic, according to Olivi ; but its
northern range is very extensive, and comprises Spitz-
bergen (Phipps, fide Scoresby); Godhaab, E. Green-
land, 50-150 f. (Wallich); S. Greenland (Eschricht);
Iceland (Mohr, Steenstrup, and Torell); Norway,
Sweden, and Denmark, 1-150 f. (Spengler and many
others); White Sea (Baer, fide Middendorff); North-
east America, from Cape Cod northwards (Gould,
Mighels, and Stimpson).

This pretty species was first noticed as British by
Professor Jamieson, in the first volume of the ' Memoirs
of the Wernerian Society ' (1811), from rocks in the
island of Unst, and almost simultaneously, in the same
volume, by Captain Laskey, from Dunbar. It may
always be distinguished from C. marginatus by its • red-
dish-brown colour, narrower and more arched shape,
broader girdle, and especially by its smooth and glossy
appearance. Young shells are longitudinally veined,
showing the internal tubular structure.

It is extremely probable that the C. ruber of Linne
may have been the species which Fabricius afterwards
described with greater precision as C. marmoreus ; and
there can be no doubt that the C. Icevis of Pennant was

l 5

226 CHITQNID/E.

the species which we are accustomed to call C. ruber.
But although Loven and his scientific countrymen have
adopted the correct names, I must confess a want of
moral courage in not following their example, believing
that the perpetuation of such trifling errors may cause
less inconvenience to conchologists in general than the
changes necessary to rectify the nomenclature of so
many species. Spengler described this Chiton as mini-
mus, and Leach (but not Lowe) as latus.

9. C. LiEvis"^ (Pennant), Montagu.

C. Icsvis, Mont, Test, Brit. p. 2; F. & H. ii. p. 411, pi. lviii. f. 3.

Body oval, inclining to oblong, reddish brown: girdle broad,
resembling hair- cloth, covered with numerous minute and
closely packed lozenge-shaped scales or spines, which are set
horizontally with their points towards the outer margin ; it is
of a dark brick- colour irregularly flecked with white ; margin
fringed with a few scattered and caducous short pinkish spines,
which are apparently a continuation of those which cover the
girdle.

Shell convex : plates broad, solid, opaque, and glossy ; la-
teral compartments more or less distinct : sculpture smooth to
the naked eye or examined with a lens, but exhibiting under a
higher magnifying-power a series of extremely delicate striae,
running lengthwise on the middle compartment of each plate,
and towards the beak on the side compartments ; the surface
is also covered (especially the terminal plates and the side
compartments of the other plates) with small tubercles, which
are very little raised and scarcely perceptible ; these are the
bulbs or extremities of the canals that permeate the fabric of
the shell, like the tubular apparatus observable in most of the
Brachiopoda ; in young specimens the tubercles are perforated
or open ; there are likewise slight parallel lines of growth :
ridge more or less prominent, but seldom conspicuous : colour
reddish-brown, marbled or veined with white, and sometimes
variegated with green, red, pink, or brown, rarely of a uni-
form dark brick- colour : beaks strong and projecting: inside

* Smooth.

CHITON. 227

fleshcolour, more or less tinged with green, slightly shouldered:
notches deep, 16-20 on the head-plate, 15 on the tail-plate,
and 2 on each of the other plates, being altogether about 45.
L. 0-75. B. 0-4.

Yar. navicula. Smaller, narrower, and more arched.

Habitat : On rocks, stones, and old shells, from Unst
to Sark, between low- water mark of spring tides and
70 f. ; apparently not gregarious, nor so common as
some other species. The variety inhabits the west of
Scotland. C. Icevis has been noticed by foreign writers
as far north as Vadsoe, East Finmark, in 30-60 f.
(Danielssen), southward to the iEgean, in 31-80 f.
(Forbes), and Algeria (M f Andrew and Weinkauff), and
also in various intermediate places, at depths varying
from 8 to 50 f.

According to Philippi, Sicilian specimens are much
smaller than the British. The largest in my collection
came from Oban, and are upwards of an inch and a
quarter long. The proportion of length to breadth is
variable.

It is the C. corallinus of Risso, C. achatinus of Brown,
C. Cranchianus and Lepidopleurus punctulatus of Leach,
and C. DoricB of Capellini. Montagu described a seven-
plated specimen as C. septemvalvis, a name which Maton
and Rackett changed to C. discors.

10. C. marmo'reus*, Fabricius.

C. marmorens, Fabr. Faun. Grcenl. p. 420; F. & H. ii. p. 414, pi. lviii.
f. 2, and lis. f. 4.

Body oval, inclining to oblong, yellowish or reddish-brown :
girdle rather broad, membranous and thin, apparently smooth,
but microscopically pustulated ; it is dusky-brown, sometimes

* Marbled.

228 CHITONID.E.

barred with dark orange ; margin fringed with extremely
short yellowish spines.

Shell convex : plates broad, solid and opaque, somewhat
glossy ; lateral compartments distinct, not much raised, but
defined by a blunt ridge which extends from the beak on
either side to the front corner of each plate : sculpture nearly
smooth to the naked eye, exhibiting under a magnifying-power
numerous minute and slight tubercles, which usually are more
conspicuous on the terminal plates and side compartments, as
in 0. Icevis ; the parallel lines of growth are strongly marked
in adult specimens: ridge indistinct: colour reddish -brown,
variegated or speckled with white or yellow, sometimes in a
zigzag or lightning fashion : beaks very strong and prominent :
inside yellowish, tinged with pink, showing the under side or
hollow of the ridge to be striated across ; shoulders long and
narrow : notches deep, 8 on the head-plate, 9 on the tail-plate,
and 2 on each of the other plates, making 29 in all, besides
some intermediate denticles. L. 1. B. 0*6.

Habitat : Stones, shells, and sea-weed in the Lami-
narian zone, from Shetland to Scarborough (Bean) ;
eastern shores of Ireland, as far south as Dublin Bay
(Kinaghan). Fossil at Fort William (J. Gr. J.); Udde-
valla (Malm) . It inhabits every part of the Atlantic,
north of Great Britain, from Spitzbergen to Zealand,
and the coasts of North-east America, at depths of
from 7 to* 100 f. M f Andrew has recorded it as dredged
at Carthagena in 5-10 f. ; this appears to be the only
instance of a southern locality.

According to Brown, Mr. Hancock discovered this
king of the British Chitons below Tynemouth Castle
in 1809. Laskey indicated it from Dunbar in 1811.
Fabricius says that it is often found in the crops of the
Eider-Duck and Anas spectabilis. His description of
the animal and shell is most admirable; and he particu-
larly noticed the notches on the margin of each plate
or valve, as characteristic of this and other species of
Chiton. It is stated by Middendorff that the epider-

patellid^:. 229

mis of the girdle in C. marmoreus displays under the
microscrope a coverlet ornamented with erect spinules.
I have not succeeded in detecting any such armature in
British specimens ; the margin of the girdle is fringed
in this way, but the surface is merely pustulated. Spe-
cimens taken by Captain Bedford in Mull are more than
an inch and a half long.

It is the C. punctatus of Strom, who nearly a cen-
tury ago showed the resemblance between the animal
of Chiton and that of Patella ; perhaps in strictness the
specific name given by him, being the more ancient,
ought to be preferred to marmoreus. Fleming called it
C. Icevigatus, Lowe C. latus, Bean C. pictus, Couthouy
C '. fulminatus , and Leach C. Flemingius.

*

Order II. PEC TINIBBA 'NCHIA TA.

Family I. PATEL'LID.E, (Patelladce) Guilding.

Body seinioval, more or less raised above and flat beneath :
mantle thin, covering the back and sides : head snout-like,
furnished with a pair of horny jaws and a long and slender
tongue, which bristles with numerous teeth and is folded up
within the body : tentacles spike-shaped : eyes on protuber-
ances at the outer bases of the tentacles, wanting in cer-
tain kinds : r/ills forming a single row or plume of leaf-like
plates, which issue from behind the neck on the right-hand
side : foot very large and rounded, occupying the whole of the
under side.

Shell conical or cap-shaped ; apex turned towards one end,
spiral, and slightly twisted on one side, or curved, in the young
state : mouth extremely wide, forming the entire base of the
cone : central scar inside shaped like an amphora.

This family constitutes the vanguard of the innumer-
able limpet tribe. Their shells are never symmetrical,

230 PATELLID.E.

as has been stated by some writers. When first formed
they are either spiral or else eccentrically twisted ; the
spire or twist is worn away in the course of growth.
There being no communication between the mantle and
the apex of the shell, the latter cannot be absorbed by the
animal. The sexes are separate. Those kinds which inha-
bit the littoral and laminarian zones are phytophagous ;
and the others, which inhabit the coralline and deep-sea
zones, are probably zoophagous. In Loven's scheme of
the dentition in univalve mollusca the rhachis or central
plate in Patella and Helcion has six teeth, and each of
the pleurse or side plates three teeth ; in Tectura the
rhachis has from four to six teeth, and the pleurae have
none ; in Lepeta the rhachis has only a single tooth,
and each of the pleurse two. Such differences may in-
dicate the nature of the food ; the first three genera are
known to live on sea-weeds, while the last (as well as
Propilidium) cannot derive their subsistence from any
vegetable matter except diatoms.

Genus I. PATE'LLA* Lister. PL V. f. 3.

Body convex : mantle fringed at its edge with cirri of irre-
gular lengths : tentacles rather short : eyes prominent : gills
numerous and closely packed, lying between the mantle and
the foot, and only interrupted on the right-hand side : foot
thick and muscular.

Shell conical, more or less convex, furnished with ribs that
radiate from the crown, having in its embryonic state a com-
pletely spiral apex ; crown prominent, eccentric but not
very much on one side ; the attachment of the mantle to the
shell is exhibited in the middle (between the crown and the
margin) as a ring-like scar.

The \67ras of the Greeks, with whom it appears to
have been rather a favourite article of food. In the

* A small pan.

PATELLA. 231

' AeiTTvoa o(f) car aV of Atheii8eus,Icesius says that it is even
more appetizing than the oyster, although not so diges-
tible; Diphilus does not hold it in such esteem. The
tenacity with which it adheres to the rock was well
known to ancient writers. This is compared by Aristo-
phanes with the attachment of an old woman to a youth ;
and iElian remarks that, when touched, it is as difficult
to remove as a pomegranate was from the fist of Milo.
In one of the odes of Alcseus it is apostrophized as the
child of the rock and hoary sea ; and Cicero refers to it
(although not by name) as an example of the sedentary
nature of some marine animals, " partim ad saxa nativis
testis inhserentiuin.'" With his usual power of observa-
tion, exceeding that of many subsequent naturalists,
Aristotle described the habits of the limpet, and showed
that it leaves its place on the rock and goes out to feed.
This was confirmed by Reaumur, although Borelli and
others asserted that the limpet remained all its life
fixed to the same spot. It uses its foot like a snail, but
travels more slowlv. Bouchard-Chantereaux savs that he
had often seen limpets crawling, especially just after the
tide had gone out. The young limpet moves freely about,
and shifts its quarters ; but after attaining a growth of
probably a few days, it affixes itself to a particular spot,
which it only quits, when covered by the sea, on the
return of each tide. If it settles on a hard and rugged
rock, the circumference of the shell is moulded to fit
the irregular surface of its abode ; the base of attach-
ment is then bleached. Should the rock be soft, it
scoops out by degrees with its muscular foot a cavity of
a greater or less depth. Mr. Anderson of Wick (the
highly intelligent editor of the ' John O' Groat Journal 3 )
gave me some pieces of Old Red sandstone from that
coast, in which the pits made and inhabited by P. vul-

232 patellidjE.

gata were so deep, that little more than the crown of
the shell was visible ontside. On the Dorsetshire coast
the chalk-rocks are also excavated in the same manner,
but not so deeply. Specimens are not unfrequently
found on impure limestone, which are constricted or
indented at the edges, in consequence of the excavation
having been hindered by the greater hardness of one
side of the spot occupied by these limpets. The animal
feeds on small delicate sea- weeds of a foliaceous kind, as
well as on Melobesia polymorpha, that encrust the rocks
at low water, by means of its long tongue, which is coiled
spirally, like the mainspring of a watch set round with
spring- cogs. This instrument is thrust out from side
to side ; and when charged with food, it is withdrawn
into the stomach, unloaded, and again put forth. The
mark left on the face of a rock, coated with a film of
the fine sea-weed mentioned above, by a limpet after
grazing resembles the track of a sea-worm : indeed a
late eminent geologist had a large slab thus marked cut
out of the rock, and sent to him with great care, in
order to publish the supposed discovery of a new Anne-
lidan ichnolite in the old red sandstone; fortunately
the mistake was pointed out to him before proceeding
further. Each limpet appears to have its own feeding-
ground or pasturage ; its tracks are sometimes numerous,
and deviate in different directions. Mr. Peach has
ascertained that it does not retire in the winter to deeper
water on the coast of Caithness, and that it always
returns home before the ebbing tide leaves it dry. Its
firm adhesion to the rock is extraordinary. In order to
test the strength of its tenacity, Reaumur suspended a
weight of from 28 to 30 lbs. from the shell of a limpet
attached to a stone ; this weight it sustained for some
seconds : less weights failed to overcome its resist-

PATELLA. 233

ance. He attributed the adhesive force not to muscular
action, but to an invisible glue which exudes from the
granulated base or sole of the foot. It may be also
caused by an adaptation of the surface of this part of
the animal to the frequent, although often minute,
inequalities of the stone; although the glutinous and
viscous fluid, which is secreted by numerous glands in
the foot, appears to be the principal agent. It is said
that death does not destroy the cohesion ; but I do not
see how such an experiment could be tried. Dr. John-
ston, in his ' Introduction to Conchology/ likewise states
that if, after having detached a Patella, one's finger be
applied to the foot of the animal, or to the spot on which
it rested, the finger will be held there bv a very sensible
attraction ; and that if the spot be then moistened with
a little water, no further adhesion will occur, the glue
having become dissolved or weakened. When the
limpet wishes to leave its abode, it has only to raise
gently the edges of the foot to admit the sea and loosen
the cement. Adanson believed that the adhesion was
owing to the action of numerous hemispherical suckers
on the under surface of the foot, aided by a viscous
secretion ; he observed that when the animal was de-
tached from the rock, those suckers expanded or assumed
a globular form. The foot is undoubtedly capable of
considerable dilatation and contraction, and has a vas-
cular structure ; it is often much distended with water.
This great French naturalist does not seem to have
known the branchial organization of Patella; for he
describes the gills as an appendage of the mantle. It
was supposed by Cuvier that the common limpet was
hermaphrodite. Adanson and Milne-Edwards, however,
established the fact of its bisexuality ; and Lebert and
Robin published in the ' Annales des Sciences Naturelles '

234 PATELLID.E.

for 1846 further particulars of its reproductive organs.
The last-named physiologists noticed that at the end of
April these organs (which in each sex are placed at the
left-hand side of the body) were wanting in nearly one-
half of the individuals dissected by them, and that of
the remainder the males were in the proportion of 3 to
8 or 10 of the females. Fischer has given us some
information as to the mode of its oviposition. This
takes place in the months of March and April, when all
the rocks at low water, as well as the shells of old
limpets, are covered with an immense quantity of the
fry. He is of opinion that immediately on the eggs
being excluded from the ovary, they are developed and
attach themselves. Gray suspected the sexes to be
distinct in the limpet ; although he could not discover
any external difference in the animals, except a slight
variation of colour. He says that in autumn he found
a white, milky, glairy fluid in some individuals, and ova
in others. My late friend Dr. Lukis noticed, in taking
up a limpet while in the act of crawling, that young
ones were attached to the under side of the foot ; and he
inferred that it carried its offspring about with it for
protection. But it is more probable that the fry became
accidentally entangled in the gelatinous fluid which
exudes from the foot, than that the phenomenon which
he observed was an instance of molluscan aropyi].
The shell represents part of a cone whose section is an
irregular ellipse. It is composed of three layers, as in
many other univalves. According to Carpenter the
inner and outer layers in Patella are rather less compact
than usual; the middle layer is'" composed of tolerably
regular polygonal cells, which form only a thin layer in
some parts, whilst in others they are elongated into
prisms."

PATELLA. 235

Gaza, a Byzantine philologist who flourished in
the 15th century, appears to have been the first to
give this shell the name of Patella. It was, notwith-
standing, called by the ancient name Lepas by other
writers, and even as late as 1616 bv Colonna. Al-
drovandus included the genus with Balanus : Lister
had the merit of separating and distinguishing them.
Nor have all modern zoologists been uniformly success-
ful in recognizing the natural position of Patella among
the Mollusca. In the opinion of Lamarck it belongs to
the same family as Phyllidia ; but the gap between the
Pectinibranchs and Nudibranchs seems much too wide
to be bridged over by even his engineering. Most of
his followers placed Patella alongside of Chiton in the
order Cyclobranchiata. The present genus was for some
time the receptacle of miscellaneous and incongruous
organisms. Among these were Patella unguis, Linne
{Lingula), P. anomala, Miiller {Crania), P. orbiculata,
Walker (according to Mr. Norm an " the calcareous disk
of the termination of a tentacle of Echinus "), P. extinc-
torium and P. tricornis, Turton (opercula of species of
Serpula) : Ancylus fluviatilis and A. lacustris were also
placed in the same genus. Patella, as now restricted, is
very rich in species, although their tendency to vary is
so great that the number of those described by authors
is evidentlv excessive. All of them inhabit rocks and
shingly beaches, and are strictly littoral. The distri-
bution of the genus is world-wide. As to its fossil
ancestry, Searles Wood says, " Shells of this form have
early made their appearance, and several have been
figured from the secondary formations/' De Montfort,
perhaps for the sake of variety, changed the generic
name to Patellus.

236 patellid^e.

Patella vulgata*, Limie.

R vulgata, Linn. S. N. p. 1258; F. & H. ii. p. 421, pi. lxi. f. 5, 6.

Body brownish-yellow or dusky, with a bluish tinge : mantle
fringed with slender cirri or filaments of different lengths and
sizes, which correspond with the ribs and striae of the shell ;
some of these cirri above the head are much longer than the
rest, and are in the proportion of 1 to 4 or 5 of the latter ;
the mantle is often edged with a narrow band of a darker
colour: head short, bulging, and strong: mouth provided with
two lips, which are placed laterally : tentacles awl-shaped, not
retractile, darker at their tips ; they curl towards each other
and lie flat on the head, when the animal is at rest: eyes
small, on slight eminences outside the swollen bases of the
tentacles : gills of a drab or yellowish colour ; branchial artery
transparent, thicker, and funnel-shaped at its origin, and
having smaller veins issuing from it during its course, at a
right angle : foot attached to the rest of the body by a series
of powerful but short interlacing muscles ; the sole is lead-
coloured, or more or less deeply tinged with yellow ; margin
thin with a pale border.

Shell forming usually a regular and somewhat raised cone,
solid, opaque, and of a dull hue : sculpture, numerous ribs,
which radiate from the apex and become stronger and broader
at the lower part or margin ; between each rib are 2 or 3 (some-
times more) parallel striae or finer ribs ; in some specimens the
ribs are irregularly granulated or studded with knob-like
tubercles ; the surface is also covered in fresh and less rubbed
specimens with close-set microscopical longitudinal lines, and
with numerous but irregular concentric lines of growth :
colour greyish or pale brownish-yellow, with often purplish
longitudinal rays arranged in duplicate ; it is rarely speckled
with white, or of a uniform dusky hue : beak or apex blunt,
often worn so as to expose the crown, which is of a reddish or
orange tint ; it is sometimes nearly central : mouth or aper-
ture roundish-oval, with the broader part behind : margin
scalloped or indented by the ribs and intermediate striae : in-
side nacreous and glossy, often yellow or exhibiting the coloured
rays (especially at the margin) ; it is minutely but irregularly
lineated in a concentric direction from the margin to that part
which is always covered by the edge of the mantle, and micro-

* Common.

PATELLA. 237

scopically fretted in the last mentioned part ; margin bevelled :
annular scar broad : central scar of every colour from white to
dark brown. L. 1-75. B. 1*5.

Var. 1. elevata. Shell much smaller, rounder, and higher.

Yar. 2. picta. Shell smaller and thinner; with alternate
rays of reddish and dark blue.

Yar. 3. intermedia. "Animal black or dark-coloured"
(Knapp). Shell rather smaller, natter, and oval, with finer
ribs, and an orange crown ; inside golden-yellow, or tinged
with neshcolour (occasionally creamcolour) in the centre, and
beautifully rayed towards the margin.

Yar. 4. depressa. Body creamcolour ; mantle fringed with
yellowish- white or pale drab cirri ; foot light oraugecolour.
Shell usually much depressed., and more oblong than the ordi-
nary form ; ribs finer but sharp ; beak nearer to the anterior
end; inside porcellanous, with a pale orange head-scar or
spatula. P. depressa, Pennant, Brit. Zool. iv. p. 142, tab.
lxxxix. f. 146 (not P. depressa of Gmelin) ; P. athletica, F. & H.
ii. p. 425, pi. lxi. f. 7, 8.

Yar. 5. ca'mdea. Shell depressed, roundish-oval; ribs
more delicate, and less regular : inside dark blue. P. ccerulea,
Linne, S. N. p. 1259.

Habitat : Between tide-marks, on rocks and stones,
everywhere, most plentiful. The first variety occurs
in North Devon, the opposite coasts of South Wales, and
at Sark. The second is not uncommon in the Channel
Isles. The third is also from the Channel Isles, where
the late Dr. Knapp first noticed it ; and Mr. J. D.
Humphreys found it at Cork. The fourth frequents
rocks onlv at low water : it is the P. Tarentina of
Lamarck, P. Bonnardi of Payraudeau, and P. athletica
of Bean. It is in most cases easy to separate this from
the ordinary form ; but the variety intermedia connects
the two, and I cannot find a single permanent character
which will serve to distinguish any of them. The colour
of the animal is of every hue and shade ; nor is the
shell less variable, taking into account the shape, height,

238 PATELLIDJL

position of the apex, sculpture, and inside lining. I
once considered myself an adept at picking out the
variety depressa (or " China limpet/' as it has been
called) by merely seeing the outside ; but I have since
failed, and a recent examination and comparison of a
great many living individuals of each form has quite
convinced me that they are not separate species. The
fifth variety inhabits flat stones and slabs of rock at low
water, often in places where streams empty themselves
into the sea ; in its younger state it is the P. aspera
of Philippi. The common limpet is fossil in raised
beaches, including that near Macclesfield at a height of
500-600 ft. (Darbishire), Moel Tryfaen, 1300-1400 ft.
(Capt. Lowe), Fort William 10 ft.(J.G.J-), and the Red
Crag (S. Wood); Uddevalla (Hisinger and Malm); newer
glacial formation near Christiania, 120 ft. (Sars); Palermo
(Philippi) . Its distribution in a recent state comprises
every coast between the Loffoden Isles (Sars) and the
iEgean (Forbes); and Weinkauff has enumerated it as
an Algerian species. The variety intermedia has been
found in Brittany by Cailliaud, and in Spain by
M f Andrew. Philippi noticed the variety depressa as
fossil in an ossiferous cavern at Mardolce, in Sicily ; and
it inhabits the shores of France, Spain, Italy, Greece,
and North Africa.

The limpet appears to have formed a considerable part
of the food of the primitive inhabitants of North Britain,
where heaps of their shells are continually being turned
up. In the ruins of a so-called Pictish fort near Ler-
wick the shells are partially calcined; and those of
the common periwinkle, which are also found there,
must have been subjected to the action of fire in order
to extract the animals. Roasted limpets are capital
eating. A few years ago I was a guest at a dinner-

PATELLA. 239

party in the little island of Herm. The hour was un-
fashionable, one o' clock ; and the meal was served on
the turf in the open air. This consisted of fine limpets,
laid in their usual position, and cooked by being covered
with a heap of straw, which had been set on fire about
twenty minutes before dinner ; there was also bread and
butter. The company were a farmer, two labourers, a
sheep-dog, the late Dr. Lukis, and myself. We squatted
round the smouldering heap, and left on the board a
couple of hundred empty shells. The limpet used to
be eaten by the Faroese ; and in Ireland and the north
of England the consumption was prodigious between
twentv and thirtv years ago, according to the accounts
furnished by Mr. Patterson and the late Dr. Johnston.
The former estimated that 11 5 tons of boiled limpets
were sold in one season about Larne, co. Antrim ;
and the latter states that nearly twelve millions had
been collected yearly on the coast of Berwickshire, until
the supply was almost exhausted. These quantities were
exclusive of what were collected to feed the pigs and
poultry. The Shetlanders are either more fastidious,
or prefer real fish ; they will not even eat an oyster.
Some of the Orkneymen seem to be imbued with a
similar prejudice ; for we find in the life of Sir Walter
Scott, that " the inhabitants of the rest of the Orcades
despise t those of Swona for eating limpets, as being the
last of human meannesses/'' The limpet is not omitted
in the old pharmacopoeia ; and Rondeletius prescribes it
eaten raw as a gentle purgative. It is a most taking
bait for coal-fish. In Shetland it is chewed by the
fishermen, and spat into the sea to attract a shoal ; this
they call " sowing/'' The yellow or " ware-limpet "
(var. depressa) is preferred by them as bait ; but
according to Bean and Alder it is rejected by the fisher-

210 PATELLXDJL

men in the north, of England. Sea-fowl of all kinds
are also fond of the limpet. The bill of the oyster-
catcher is said to be admirably adapted for forcing it
from the rock ; and the pions Derham tells ns that
ff the Author of Nature seems to have framed it purely
for that use/' Something must now be said for the limpet
itself, as well as about its persecutors. It appears from
the experiments of Beudant to have an unusual capa-
bility of living in fresh water. This may be accounted
for by its littoral habit, which exposes it to rain and
the efflux of streams into the sea, as well as to the con-
tinual percolation of fresh water which takes place on
shingly beaches. The animal is occasionally monstrous.
Fischer noticed a limpet on the French coast which had
the left tentacle branched or double, with two eyes at
its base. The shell is as much entitled to the name
potymorpha as to that of vulgata. In the ' Zoologist''
for October 1860 will be found an excellent remark by
Mr. Norman, as to the variation of its form resulting
from habitat ; and I cannot do better than give it in
his own words. " It will be found to be a general rule
with regard to the limpet, that the nearer high-water
mark the shell is taken, the higher- spired, more strongly
ribbed, and smaller it will be ; and that the lower down
it lives, the natter, less ribbed, and larger it becomes/''
In the intermediate space, and under local conditions,
other forms of course occur, which partake of some of
the above characteristics in a modified degree. Speci-
mens which I found in a particular spot at Lerwick
were excessively thin, and as if they were exfoliated,
probably owing to a deficiency of calcareous material.
One shell from Balta Sound is of an extraordinary
thickness and weight : it had been inhabited by a
colony of the burrowing cirriped, Alcippe lampas; and

PATELLA. 241

the poor limpet must have spent much of its time, as
well as all its substance, in adding layer after layer to
provide a roomy lodging for its troublesome parasites.
In some specimens the crown is depressed, the rest of the
cone being considerably raised. The inside of old shells
is often garnished with irregular pearly excrescences.
My largest specimens were taken at Lulworth, and on
Uyea Island; they measure £| inches by 2J. The va-
riety depressa is very pretty, and especially when the
interior is streaked with violet-brown rays on a porce-
lain ground. So is the variety picta. In Da Costa's
time such shells were called by the English " Auriculas "
and by the French " Soucis "• or marigolds, from their
resemblance to those flowers. The spire of the very
young shell is slightly twisted on one side, with an in-
clination to the posterior or broader end ; it has one
whorl and a half. The tongue is rather longer than the
shell ; and, according to Forbes and Hanley, it is armed
with 160 transverse bands of teeth, each band having 12
teeth, or 1920 in all. Mr. Spence Bate has examined
the lingual ribbon in the variety depressa. This is
broader and shorter than in the common kind, but offers
no other distinction than that the teeth are perhaps
somewhat larger.

It is the P. vidgaris of Belon, Petiver, Da Costa, Landt,
and others. Gmelin divided it into a great many species,
chiefly from the descriptions of Schroter. The local
names are innumerable. De Montfort reckons no less
than fifty-two. I will cite a very few only — " flither"
of the English, " flia " of the Faroese, ' f *flie " of the
Normans, " ceil de bouc " of the French, and " lapa "
of the Portuguese.

VOL. III. M

242 PATELLID^E.

Genus II. HEL'CION * De Montfort. PL V. f. 4.

Body convex : mantle fringed at its edge with cirri, which
are alternately long and short : tentacles rather long : eyes pro-
minent : tongue shorter than in Patella : gills not so numerous
as in that genus, and forming a shorter plume, which is in-
terrupted over the head : foot thick, of a cellular texture.

Shell cap-shaped, having in its embryonic state a slightly
twisted apex ; crown never prominent, but inflected towards
the anterior end, and placed near the margin — especially in the
young, where it is almost terminal : scars slight and indistinct.

Besides the differences in the arrangement of the
pallial cirri, and in the shorter branchial plume, the
shell may always be known from that of Patella by its
shape being semioval instead of resembling a peaked
hat ; the crown is incurved, and the apex nearly ter-
minal in the present genus. The fry is not spiral, as
in Patella. The shell of Helcion is also usually a
thinner shell, with an opalescent hue ; and in the only
species that we possess the surface is smooth, or never
distinctlv ribbed. Helcion is found on Laminarias and
sea-weeds of a similar kind, which constitute its food ;
and it is therefore sublittoral in its habits. The species
are few, but have an extensive range, including Europe,
West and South Africa, Cape Horn, and Australia.

It is the genus Nacella of Schumacher, Patina of
Leach, and partly Calyptra of Klein.

Helcion pellu'cidum f, Linne.

Patella pellucida, Linn. S. N. p. 1260; F. & H. ii. p. 429, pi. ki. f. 3, 4,
and (animal) pi. A A. f. 1.

Body creamcolour, with a slight tinge of brown in front :
mantle often bordered by a grey or leadcoloured line, and
fringed with from 30 to 65 fine white cirri, half of which are
more than twice as long as the intermediate ones : head trans-

* A breast-collar. f Transparent.

HELCIOX. 243

verselv triangular : mouth minutely scalloped or puckered :
tentacles slender : eyes small : gills of a whitish colour : foot
oval, equally broad at both ends ; sole yellowish-white, edged
with a narrow brown line.

Shell resembling the " cap of liberty," convex, semitrans-
parent, and glossy : sculpture, sometimes very slight and in-
distinct angular lines, which radiate on all sides from the beak,
and vary in number and regularity ; the surface, however, is
frequently quite smooth ; it is covered with numerous and
close- set microscopical concentric striae, which in old shells are
raised into distinct marks of growth : colour yellowish-brown of
different shades passing into horncolour, and adorned with
from 25 to 40 narrow bright blue streaks on a brown ground ;
these streaks radiate from the beak, and are more or less in-
terrupted ; crown marked with a dusky spot and occasionally
with a short linear ray of the same colour : heal: sunk below the
level of the crown and inconspicuous : mouth oval : margin
compressed at the sides, even and smooth : inside shining and
polished, as if highly glazed, opalescent or lilac in adult shells.
L. 0-8. B. 0-6.

Yar. laevis. Shell more or less solid, opaque, compressed, and
expanded. Patella l&vis, Pennant, Brit. Zool. iv. p. 144,
pi. xc. f. 151.

Habitat : On Laminariae at low water (and as deep
as 15 f., Forbes and M f Andrew), on all onr coasts ; the
young are sometimes also found on the under side of
large stones which are uncovered at spring tides.
Mr. James Smith has enumerated it as fossil from Dal-
rnuir, Ayr, Banff, and Ireland ; and Sars, from the newer
glacial formation near Christiania, at a height of 100 ft.
Living in the Faroe Isles (Morch) ; North Cape
(Danielssen) ; Scandinavia, from the shore to 20 f.
(Brander, Loven, and others) ; Heligoland (Frey and
Leuckart); coasts of France (De Gerville and others);
Vigo, 8 f., and Cascaes Bay, 15-20 f. (M' Andrew);
Mediterranean (Linne); Sicily (Maravigna); Mogador,
littoral to 3 f. (M'Andrew and R. T. Lowe) . The variety

m 2

244 PATELLID.E.

seems to have an equally wide distribution, although
Loven says that he had not met with it.

Lister figured both forms of the " blue-rayed limpet/'
or "peacock's feathers/' The young attach themselves to
the upper side of the fronds of the smooth tangle (Lami-
naria saccharina) , and sometimes of L. digitata, (accord-
ing to Mace, Halymenia palmata also,) which supply them
with succulent and abundant pasturage : when it grows
older, it attacks the stalks, and afterwards gets to the
base of the plant, into which it eats its way until it be-
comes almost buried in a cup-shaped cavity; it is then fat
and lazy. The best way of procuring such last mentioned
specimens is to tear up by its roots the large tangle, which
girdles the rocks at low water, and waves forwards and
backwards like a field of ripe corn in a summer breeze.
As, however, it is not an easy matter for a lady collector
to do this, she may avail herself of the next storm, and
hunt for the pretty prize among the sea-weeds thrown
up on the beach. This remarkable habitat was first
noticed by M. le Gentil, in the ' Memoires de TAca-
demie ■ for 1788. If it had been known to English na-
turalists, so many of them would not have persisted
in considering the ordinary form on the leaves and the
variety imbedded in the roots as different species. The
crown is the same in each. The animal crawls with an
undulating motion. Some individuals, which I observed
in a glass vessel of sea-water, now and then protruded
their jaws and the front of their tongues, apparently for
the purpose of cleaning their teeth; and after doing
this, they ejected from the mouth a thick fluid of a
brownish colour — possibly the scrapings of the lingual
ribbon. The beak is almost terminal in young shells.
Specimens taken from the stalks of Laminaria at Dover
and in North Wales are fully an inch long, although

TECTURA. 245

very convex, thin, and beautiful. They evidently would
never have assumed the shape of the variety.

It is the Patella intorta of Pennant, P. minor ox
Wallace, P. cceruleata of Da Costa, P. ccerulea of Mon-
tagu (but not of Linne), and P. cornea of Michaud.
The very young is Montagu's P. bimaculata. Couch's
shell of the last name was apparently a simple Ascidian,
perhaps a species of Cynthia.

H. pectinatum [Patella pectinata, Linne) was wrongly
admitted into British catalogues on the authoritv of
Laskey. Linne gives as its habitat the Mediterranean ;
Payraudeau, Corsica; and R. T. Lowe, Mogador and
Senegal.

Genus III. TECTU'RA* [Tecture) Cuvier. PLY. f. 5.

Body more or less depressed : mantle fringed at or near its
edge : tentacles variable in length : eyes prominent, wanting
in some species : gills forming a short plnme, which is free,
and contained in a cavity over the neck on the right-hand side
of the head ; it is extensile, and sometimes protruded beyond
the shell : foot of moderate thickness.

Shell conical, usually depressed, furnished with striae which
radiate from the crown, having in its embryonic state a curved
or semispiral apex ; crown not prominent, but projecting hori-
zontally, and placed near the front margin : pallia! scar nearly
marginal.

I do not see any reason for placing this genus in a
separate family from that which includes the last two
genera. The difference in the length of the branchial
apparatus, on which so much stress has been laid by
some conchologists, is comparatively unimportant. In
each of these three genera the gills compose a single
row or plume, which is elongated and attached through-
out in Patella, and less so in Helcion ; while in Tectura

* A covering over.

246 PATELLID^E.

it is short and free, except at the base. Loven, who is
certainly not inferior to any one in his knowledge of
the organization of the Mollusca, reunites all in the old
genus Patella. Certain species are eyeless ; but the
genera Eulima, Mangelia, Cylichna, and Amphisphyra
offer analogous cases of such a deficiency of the so-
called visual organs.

The name Tectura has the precedence of Acmcea
(Eschscholtz) by three years. It was originally Tecture ;
and although the termination is not Latin, I am inclined
to adopt it as now spelt, in justice to Audouin and
Milne-Edwards, the distinguished French zoologists,
who first indicated the genus, as well as to Cuvier, who
afterwards named it and defined the characters in his
report to the Academy of Sciences in 1830 on their
account of the Invertebrata of the French coasts. The
name A cmcea, besides, is objectionable, being derived from
an adjective. Quoy and Gaimard called this genus
Patelloidea, and Gray Lottia. Forbes proposed to form
another genus, with the name of Iothia (afterwards
changed by him and Hanley to Pilidium), for one of
the species. The Tectura? inhabit both the Atlantic and
Pacific Oceans ; and some have been found in the newer
tertiary strata. Their bathymetrical range is extensive.
The littoral species have eyes, while those living in deep
water have none.

1. Tectura tes'tudina'lis *, Miiller.

Patella testudinalis, Mull. Prodr. Zool. Dan. p. 237. AcnicBa testudinalis,
F. & H. ii. p. 434, pi. lxii. f. 8, 9, and (animal) pi. A A. f. 2.

Body white : mantle covered with vibratile cilia ; margin
fringed with minute white cirri : head large, somewhat rounded
and convex : tentacles awl-shaped, long, and slender : eyes
small : gills whitish, lanceolate, and ciliated : foot oval and
very broad, with plain and nearly level sides.

* Like tortoiseshell.

TECTURA. 247

Shell depressed, rather thin, opaque, and devoid of lustre :
sculpture, numerous very fine and sharp longitudinal striae,
which radiate from the beak ; they are not visible by the naked
eye ; the surface is also covered with close-set and almost mi-
croscopical concentric striae, varied by occasional lines of
growth that are more conspicuous : colour greyish with dark
reddish-brown longitudinal streaks, which often are confluent
and forked, giving a tessellated or clouded appearance like that
of tortoiseshell ; sometimes the colour is reddish-brown varied
by broad rays or spots of white : beak rather sharp, placed
usually about one-third nearer the anterior end: mouth roundish -
oval : margin expanded, even and smooth : inside shining and
polished, except at the margin, chocolate-colour in the centre
or dorsal scar, porcelain-white and highly glazed in the
middle, and of a dull hue at the margin, which is rather
broad and bevelled to a sharp edge. L. 0-85. B. 0*7.

Habitat : On the under side of stones, at low water
and as deep as 20 f. in the laminarian zone, Shetland
Isles (Barlee); Orkneys (M f Andrew and Thomas);
Caithness (Peach); Sutherlandshire (J. G. J.); Aber-
deenshire (Macgillivray) ; Moray Firth (Gordon and
others); west of Scotland (Brown and others); Belfast
(Hyndman) ; Lough Strangford (Dickie); Bangor, co.
Down (Clealand); Dublin Bay (Lloyd and others); Isle
of Man (Forbes) ; Berwick Bay (Howse) ; Northumber-
land and Durham, as far south as Hartlepool (Hancock
and others), and living in 40 f. (Alder). It is also
common and widelv distributed throughout the Arctic
and North Seas from Greenland to Iceland, and. from
Nova Zembla to the South of Sweden, as well as
Canada and the north-eastern coasts of the United
States.

Forbes noticed the migratory habit of this remarkable
species, in his account of a shell-bank in the Irish Sea ;
and the Tyneside Naturalists' Field-Club have given
some curious details of its southward march. Speci-
mens collected by Captain Bedford at Oban are nearly

248 PATELLID^.

1| incli long, and one found by Mr. Macdonald in the
Moray Firth is a trifle longer ; in North America it
even exceeds these dimensions. Dr. Wallich procured
bright-coloured specimens at depths of from 50-150 f.
off Godhaab in East Greenland.

A less distinctly striated form is the Patella testudi-
naria of Miiller, although not of Linne; and the young
is the P. tessulata or tessellata of the first-named author.
It is likewise the P. Clealandi of Sowerby, P. clypeus
of Brown, P. amama of Say, and P. Clealandiana of
Leach. The P. Clealandi of Couch, from Gorran, in
Cornwall, appears to have been only a white variety of
T. virginea.

2. T. virgi'nea*, Miiller.

Patella virginea, Mull. Prodi*. Z. D. p. 237. Jcmcsa virginea, F. & H.
ii. p. 437, pi. lxi. 1'. 1, 2.

Body milk-white or pale yellowish-white, faintly suffused
with piuk : mantle thick, fringed with unequal filaments
a little within the margin, where it is banded with pink
at intervals corresponding to the coloured rays on the shell :
head having a rosecolour tinge, very short, broad, and semi-
circular, furnished with a lappet on each side : tentacles rather
long, contractile, and ciliated : eyes small : gill-plume falciform,
of the palest drab, coarsely pectinated, also contractile and
ciliated : foot roundish-oval, smooth, delicately veined with
white.

Shell most commonly depressed, more or less solid, according
to habitat (specimens from the laminarian zone being thinner
than those found between tide-marks), opaque, somewhat
glossy : sculpture, numerous fine thread-like strise which ra-
diate from the beak ; these, however, are often indistinct and
apparently wanting ; concentric stria? and marks of growth
as in T. testudinalis : colour yellowish-white, with a pinkish
tinge and from 16 to 20 pink or brownish longitudinal rays,
which are rather broad, and are occasionally interrupted or
spotted with white, so as to give an appearance of coloured

* Maidenly, or graceful.

TECTURA. 24'j

chainwork : beak rather sharp, placed near the anterior end,
which it sometimes overhangs : mouth usually more round
than oval, but variable in this respect: margin even and
smooth : inside highly polished, porcelain-white or pinkish,
and frequently exhibiting in tlie young near the crown two
of the outside rays, which are darker than the others and
assume the shape of a reversed V ; margin rather broad, and
bevelled to a sharp edge : paUial scar marked on the inner
line with a row of several white dots, that probably corre-
spond with the fringe of cirri on the mantle. L. 0*4. B. 0-3.

Yar. 1. conica. Shell much smaller, more conical, and higher,
with the crown nearly central.

Yar. 2. lactea. Shell milk-white.

Habitat : Common on shells and stones in the lami-
narian zone, and occasionally at low water, throughout
the British Isles. Var. 1. occurs in deeper water. Yar. 2.
Scarborough (Bean). Fossil in the Scotch and Irish
newer pliocene beds (J. Smith, Forbes, Janiieson,
Crosskey, and J. G. J.) ; Uddevalla (Malm) ; Chris-
tiania, 120-200 ft. (Sars) ; Calabria and Tarento
(Philippi) ; Red Crag (S. Wood). It is found living in
every part of the North Atlantic, from Iceland (Torell)
to the Canary Isles (M f Andrew) and Azores (Drouet),
as well as on both sides of the Mediterranean, and in
the iEgean (Forbes) ; perhaps also at Sitka Island as
Patella pileolus or P. Asmi of Middendorff. The range
of depth varies in these foreign localities from 3 to 60 f.

Specimens taken by Mr. Jordan on the shore at
Guernsey are larger and thicker than any other which
I have seen ; their diameter exceeds half an inch. The
apex of the fry is white, and has an incomplete
whorl.

The little pink-rayed limpet ;has had many hard
names given to it, besides those of Middendorff. It is
the Patella minima of Gmelin (from Schroter), P. parva
of Da Costa, P. cequalis of J. Sowerby, Ancylus Gussonii

M 5

250

PATELLID.E.

of Costa, Patelloides vitrea of Cantraine, Patellapellu-
cida of Philippi, and P. pulchella of Forbes.

3. T. FULf a * Miiller.

Patella fulva, Mull. Prodr. Z. D. p. 237. Pilidium fulvum, F. & H. ii.
p. 441, pi. lxii. f. 6, 7, and (animal) pi. A A. f. 3.

Body whitish : mantle fringed at the margin with fine short
transparent cilia : head prominent, furnished beneath with two
triangular lappets, one on each side : tentacles conical and
short, not bearing any tubercle or eye-stalk : eyes none : foot
oval, thick, occupying a space equal to about two-thirds of the
mouth or base of the shell.

Shell cap-shaped or semioval, rather thin, semitransparent,
lustreless : sculpture, numerous line and sharpish ribs which
radiate from the beak ; their crests are minutely beaded ; the
concentric striae are as close-set as in other species, but are
much stronger and somewhat imbricated; the shell appears
under the microscope to be permeated by exceedingly fine
longitudinal lines : colour orange, bright reddish-brown, or
yellow, sometimes diversified by white rays of various widths :
beak sharp, placed very near the anterior end : mouth oval :
margin very thin, slightly scalloped by the ribs : inside highly
glossy, coloured like the outside : central scar forming a semi-
circular lobe in front and an oval one behind: pallial scar
too faint to be perceptible. L. 0-25. B. 0*185.

Yar. 1. albula. Shell white.

Var. 2. expansa. Shell larger, more depressed, and broader
in proportion to the length.

Habitat ; Common on stony ground in 10-40 f., in
many parts of the west of Scotland; Moray Firth
(Dawson) ; twenty miles off Kinnaird's Head, Aberdeen-
shire, in 30 f. (Thomas) ; Shetland, 40-90 f. (M<An-
drew and others) ; Cork Harbour, on Pinna rudis
(Humphreys) ; Youghal, with Crania anomala (Miss
M. Ball); off Cape Clear and Mizen Head in 50-60 f.
(M f Andrew) ; west of Ireland, 100 f. (Hoskyns, fide
King). The 1st variety is found occasionally with

* Deep yellow.

LEPETA.

251

coloured specimens ; and the 2nd is Zetlandic. I am
not aware that T. fulva has been found fossil in this
country. Mr. Searles Wood's specimens from the
Coralline Crag, which he described as this species, ap-
pear to belong to Lepeta cceca. Sars has enumerated it
among the shells from the older and newer glacial for-
mations near Christiania ; in the former at a height of
400-440 ft., and in the latter at 120 ft. Its foreign
habitat is entirely Scandinavian, and comprises all that
coast between Finmark and Bohuslan, its bathymetrical
range extending from 10 to 160 f.

The animal swims or floats in an inverted posture,
but slowly. Its lingual apparatus does not seem to
differ materially from that of T. testudinalis or T. vir-
ginea. In all of them the central teeth are square, and
the laterals elongated and hooked. T. fulva, however,
has but a single row, while each of the other two
species has a double row of central teeth. The shell is
often encrusted by zoophytes and sessile Foraminifera.
It differs from T. virginea in texture, colour, and
sculpture. It is never so large as that shell ; my finest
specimen is y^ths of an inch long.

This is the Patella Forbesii of James Smith.

Genus IV. LE'PETA * Gray. PL Y. f. 6.

Body depressed : mantle thick-edged : tentacles short : eyes
wanting : foot thin.

Shell conical, somewhat depressed, furnished with tuber-
culated striae, which radiate from the crown, and are crossed
by concentric lines : beak in the embryonic state curved, and
always inclining towards the rear ; crown nearly central :
joallial scar placed within the margin.

Indicated and named by Gray; defined by H. and

* Possibly derived from Lepas, the ancient name of the limpet.

ZO.Z PATELLID.E.

A. Adams. It depends on conchologieal characters.
The apex of the shell turns backwards, instead of for-
wards or towards the head, which latter is the case with
Tectum and the other preceding genera of the same
family. The animal is blind, an infirmity that it shares
with T.fulva and the succeeding genus Propilidium.

Lepeta ceca*, Miiller.

Patella caca, Mull. Prod. Z. D. p 237.

Body whitish : tentacles setose : foot large : liver green
(Miiller and Sthnpson).

Shell having an oval outline, moderately solid, opaque,
slightly glossy : sculpture, very numerous and close-set fine
striae, which radiate from the beak, and are crossed by slighter
concentric and imbricated striae, the intersection of which
causes the longitudinal striae to be granular or nodidous,
especially towards the margin ; marks of growth distinct :
colour milk-white : beetle blunt, much worn in full-grown
specimens: mouth oval: margin thin and even, minutely
tuberculated in immature specimens : inside porcelain-white,
and partly iridescent : central scar large and conspicuous :
pallia! scar rather broad and glossy, placed between the central
scar and the margin. L. 0"5. B. 035.

Habitat : Off Unst, in Shetland, at a depth of from
80 to 90 f., — Mr. Dawson having found a fine and
fresh but somewhat broken specimen in sand which I
dredged there last summer. I should not be so well
satisfied of this evidence that it is British, if it had not
been confirmed by my discovering a smaller specimen
(having the dried remains of the animal in it) among
some of Tectura fulva which Mr. Barlee dredged on the
west coast of Scotland in 1846. He was never, as I
believe, acquainted with this species, nor had any shells
from Scandinavia, where it is rather common. I may

* Blind.

PROPILIDIUM. 253

also mention that Mr. Dawson dredged several speci-
mens in the Moray Firth, bnt in apparently a semi-
fossilized state. L. cceca occurs in the Red and Coral-
line Crag ; Uddevalla (Lyell) ; Christiania district, in
the older portion of the post-pliocene or glacial forma-
tion, 400-440 ft. (Sars) ; Antwerp Crag (coll. Nyst) . It
inhabits the Arctic and North Seas, from Spitzbergen
(Goodsir) and sea of Okhotsk (Middendorff) to Gotten-
burgh (Malm), as well as the eastern and western
coasts of North America (Couthony, Stimpson, Bell,
and P. Carpenter) ; the depths in these localities vary
from 20 to 100 f.

According to Loven its dentition agrees with that
of Tectura fulva.

The present species is the P. Candida of Couthony
and P. cerea of Moller.

Genus V. PRO'PILI'DIUM * Forbes and Hanley.

PL VI. f. 1.

Body compressed: mantle finely ciliated at its edge: tentacles
rather long and slender : eyes wanting : gills, according to
Forbes and Hanley, apparently forming two short triangular
plumes, which are furnished with large cilia : foot thick.

Shell conical and much raised, cancellated, having in all
states of growth a minute spiral apex, which is inflected to-
wards the rear ; crown central : inside furnished in the middle
with a shelf-like triangular plate, ~>Iiich covers about one-half
of the crown : central scar indistinct : pallid scar situate
within the margin.

A singular genus, agreeing with Lepeta in the retro-
gressive inclination of the beak, but differing from that
and every other genus of the Patella family in always

* From its affinity to the genus Pilidium proposed by the same

authors.

254 PATELLID.E.

having a distinctly spiral apex and a plate or septum
inside the crown. The use of this last-mentioned pro-
cess is not known. It is too small to contain or support
the viscera, as in Calyptraa and allied genera ; but it
may be homologous with the internal process of Punc-
ture lla.

Propiliditjm ancyloi'de *, Forbes.

Patella ? Ancyloides, Forbes, in Ann. Nat. Hist. v. p. 108, pi. ii. f. 16.
Propilidium Ancyloide, F. & H. ii. p. 443, pi. lxii. f. 3, 5, and (animal)
pi. A A. f. 4.

Body whitish with a faint tinge of yellow : mantle fringed
at its edge with close-set but distinct cilia, which correspond
with the striae of the shell : head semicircular, margined with
light brown : mantle scalloped or puckered : tentacles tapering
to a fine point, delicately ciliated, destitute of eye -stalks :
foot oval, broader in front than behind.

Shell having an oval outline, compressed at the sides,
rather thin, semitransparent, glossy at the apex, but else-
where of a dull hue : sculpture, very numerous and close-set
fine stria?, which radiate from the beak and are exquisitely
granulated in consequence of their being intersected or decus-
sated by equal-sized concentric striae : colour dirty white,
occasionally diversified by a few clear longitudinal rays or
lines : beak smooth and highly polished, styliform and slender,
pinched up into a minute spire of between one and two whorls,
which curls downwards at the posterior end : mouth oval, of
nearly the same breadth throughout : margin thin and even,
minutely tubereulated in immature specimens : inside nacreous,
furnished in the centre with a thin laminar partition, like the
half deck of a vessel, which has its opening towards the
head or anterior part ; pallial scar broad. L. 0-15. B. 0-115.

Habitat : Not uncommon on stones and among
nullipores, in co. Galway (Barlee); Strangford Lough on
oysters, and on the Antrim Coast in 18-100 f. (Hynd-
man and others) ; Ballantrae, Ayrshire (Getty) ; Lam-
lash Bay (Smith, Forbes, and others) ; Oban, 20 f.

* Having the aspect of an Ancylus.

FISSURELLID.E. 255

(J. G. J.) ; Mull and Skye, 30-90 f. (Forbes, M< An-
drew, and Barlee) ; Moray Firth (Dawson) ; Shetland,
75-80 f. (Barlee and J. G. J.) . It has not yet been
noticed as fossil; and the only foreign locality is the
coast of Sweden, at a depth of only 12 f., with Mytilus
Adriaticus and Branchiostoma lanceolatum (Malm) .

The animal is active for its size. Forbes and Hanley
remarked that the tongue is very long, and the brown
central spines conspicuous under the microscope, re-
sembling bramble-thorns in miniature.

It was named by the late Mr. W. Thompson "Patella?
exigua, Forbes."

Family II. FISSURE'LLID^, {Fissurelladce)

Fleming.

Body conical or semioval : mantle folded in front, so as to
form a tubular process, which occupies a slit in the margin or
near the summit at that end of the shell or else a hole in the
crown : head prominent, with a short muzzle, furnished (as in
the Patellidce) with jaws and a spinous tongue, which latter is
shorter than in that family and scarcely convoluted : tentacles
spike-shaped : eyes seated on short tubercles, one at the outer
base of each tentacle : gills forming two symmetrical and
somewhat triangular plumes, one on each side of the neck :
foot thick, studded at the upper side or covered entirely with
papillae : vent anterior, placed in the middle between the gill-
plumes.

Shell cap-shaped or ovately conical, with a slit in front or
near the crown on that side, or else a hole in the centre ; it is
ribbed lengthwise and often cancellated by concentric or trans-
verse striae : beak tinned towards the hinder part, where it
forms a short and complete excentric spire, always in the young
and mostly in the adult : mouth extremely wide and occupying
the entire base.

The fissure or perforation of the shell indicates a cor-
responding formation of the animal, a fact which to this

256 fissurellid^:.

extent enables us to dispense with the so-called science
of malacology. The fewer technical words that are
used, the more easv it will be for students to learn the
language of this or any other branch of natural history.
The tubular process of the mantle apparently serves for
the admission of aerated water to the gills, as in the
Siphonobranchiata ; it has been also, but without reason,
supposed to have a faecal office. The outer layer of the
shell is laminated, the middle one cellular, and the
inner nacreous. None of the Fissurellidae can properly
be called littoral, although some of them are occasionally
found under stones at low- water mark. They are spread
over all parts of the world.

Genus I. PUNCTUREL'LA * R. T. Lowe.

PL VI. f. 2.

Body conical : mantle protruded through a slit near the
top of the shell on the anterior side, outside of which it forms
a short tubular process : foot crested with a row of papillae.

Shell cap-shaped, with a slit in front of the crown : beak
always spiral: inside furnished with a short funnel-shaped
process having its exit in the hole abovementioned.

The name Cemoria, proposed by Dr. Leach, was not
published before Mr. Lowe described the present genus ;
the type of the first-named genus is the fry of Fissurella
Gr<2ca. The Cemoria of Risso (from Leach's MS.) is a
fossil, and apparently a species of Calyptr&a. Some
conchologists have associated Defrance's genus Rimula
with that of which we are now treating : the latter has
an internal process, and the perforation is placed close to
the crown ; while the other has no such process, and the
perforation is placed midway between the crown and the
posterior margin. Rimula bears the same relation to
* Having a small prick or puncture in the shell.

PUNCTURELLA. 257

Emarginula as Schismope does to Scissurella. Other
synonyms of Puncturella are Diodora, Gray (according
to De Blainville), and Sipho, Brown.

Puncturella Noachi'na *, Liime.

Patella Noachina. Linn. Mant. Plant, p. 551. Puncturella Noachina,
F. & H. ii. p. 474, pi. brii. f. 10-12, and (animal) pi. B B. f. 4-6.

Body milk-white with a faint tinge of brown : mantle thick ;
tubular fold conical and short, furnished with six small papilla)
in front and four behind : head large and broad, bilobed :
tentacles conical and pointed, rather short, greatly diverging,
and ciliated : eyes large and prominent : foot oval, broader and
somewhat truncated in front, bluntly pointed behind ; upper
side forming a ridge, which is studded with short white conical
points (ten on each side) corresponding with the ribs of the
shell ; those in front, especially the penultimate ones near the
tail, are larger than the rest.

Shell more or less raised, slightly compressed at the sides,
rather thin, semitransparent, not glossy : sculpture, 25-30
sharpish but not much elevated ribs, which radiate from the
beak to the margin, and as many smaller intermediate ones ;
the surface is also covered with microscopical and close-set
longitudinal stria), and with minute white and glistening dots,
which are arranged lengthwise in rows, and seem to indicate
an internal tubular structure ; lines of growth slight and
irregular : colour whitish : beak small, ribless, incurved, and
twisted to the left, forming a spire of one whorl and a half:
slit lanceolate, extending from the crown some distance down
the front, and passing obliquely in that direction : mouth oval,
somewhat broader behind : margin thin, scalloped or indented
by the ribs : inside nacreous, marked with fine concentric
lines ; from the centre or crown towards the front runs a
rather large vaulted sheath, occupying more than one-fourth
of that side ; it covers the slit, which is continued in front of
the sheath in the form of a narrow groove with thickened
sides, nearly to the margin ; the sheath is strengthened at
each side by a rather solid buttress. L. 0*4. B. 0*3.

Yar. princeps. Shell higher and much narrower from being
pinched up at the sides, with the mouth consequently oblong.
Cemoria princeps, Mighels and Adams.

* So named (as a fossil) from its supposed diluvian origin.

258 fissurellidjl.

Habitat : Hard ground, from 25 to 90 f., in Shet-
land and the west of Scotland, being rather plentiful
in the latter district ; Aberdeen (Macgillivray) ; Nor-
thumberland and Durham (Alder, King, and others) ;
Scarborough (Bean) ; co. Antrim (Hyndman, Waller,
and J. G. J.) . The specimens, however, from the last-
mentioned locality are probably relics of the glacial
epoch, and not recent. The variety is rare; it oc-
curred in my Shetland deep-water dredgings. T. Noa-
china is tolerably common as a fossil in the Clyde beds ;
also at Fort William (J. G. J.); Bridlington (S. Wood);
Kelsey Hill, Yorkshire (Darbishire) ; Uddevalla (Hi-
singer); older glacial formation at Christiania, 400—440
ft. (Sars) . It inhabits every part of the sea north of
Great Britain, from Gottenburgh (Malm) to Spitzbergen
and North Greenland (Torell), at depths of from 4 to
150 f . ; Canada (Bell) ; Maine (Mighels); Massachusetts,
frequently in the stomachs of fishes (Gould) ; New Eng-
land, 20-30 f. (Stimpson) ; and the variety has been
taken also from the stomachs of fishes caught in 40-75 f.,
nearly 100 miles seaward from Casco bay.

Fabricius noticed the difficulty of keeping this mol-
lusk alive when taken from its native habitat. In the
young shell the slit is almost marginal, but recedes
further from the edge in the course of growth.

The synonyms are somewhat numerous, viz. Patella
fissurella, M tiller ; Sipho striata, Brown ; and Rimula
Flemingii, Macgillivray, who gives the following reason
for that cognomen : — " One malacologist has named it
after Noah, another after Dr. Fleming. I am unable to
determine the priority, and therefore take the living
godfather. - " Leach had called it Cemoria Flemingiana,
The fry is the Patella Zetlandica of Fleming.

EMARGINULA. 259

Genus II. EMARGFNULA * Lamarck. PL VI. f. 3.

Body conical : mantle protruded from the slit in front of
the shell, outside which it forms a short tubular process : foot
studded at the upper side with papillae : verge cirriform, on
the right-hand side.

Shell cap-shaped, with a vertical slit in front, which is
partly filled up as the shell increases in size, so as to leave a
furrow : beak always spiral : inside thickened on each side of
the slit.

These pretty shells, commonly called " slit-limpets/''
inhabit Europe, Asia, Africa, America, and Australia.
The very young resembles a Scissurella ; it has a regular
Trochoidal spire, and the outer edges of the slit are
inflected : the fry has no slit.

1. Emarginula Fiss'uRAt, Linne.

Patella fissura, Linn. S. N. p. 1261. E. reticulata, F. & H. ii. p. 477»
pi. lxiii. f. 1 (as E. Millleri).

Body white, sometimes faintly tinged with yellow or light
brown : mantle open in front; margin finely ciliated; tubular fold
forming an entrance into the branchial cavity, fringed outside
with minute papillae : head large and broad, usually protruded
beyond the foot : tentacles contractile and therefore varying in
length, flattened at the sides : eyes oval, placed on round pe-
duncles one-third of the way up from the outer base of the
tentacles : foot oval, crested above on each side ; round the
upper edge of this crest, and near its junction with the rest of
the body, is a row of small milk-white papillae or tentacular
processes.

Shell usually raised, so as to give a height in proportion
to the length as 2 to 3, solid, opaque, not glossy : scidjoture,
25-35 strong but narrow and cord-like ribs, which radiate
from the beak to the margin, and as many smaller interme-
diate ones ; sometimes these ribs are equal in size ; they are
crossed by from 20 to 30 somewhat slighter concentric ribs,

* Haying a little notch in the margin. t A cleft.

260 FISSURELLID^E.

imparting a regularly and deeply cancellated or punctured
appearance, and forming slight nodules at the points of junc-
tion ; the surface is also covered with microscopical and
close-set longitudinal striae, and in the young may be ob-
served the same white dots that have been described with
reference to Pitncturella Noacliina : colour white, often more
or less stained by extraneous matter : beak very small, rib-
less, incurved and slightly twisted to the left, forming a
spire of two whorls : slit of equal width, extending from the
margin in front about one-third of the way up, where it is
closed by a subsequent formation of shell, and becomes as
far as the crown a rather deep groove, which is somewhat
closely laminated across : mouth roundish-oval, distinctly
scalloped and notched by the indentation of the longitudinal
ribs : inside nacreous, finely lineated in a concentric direc-
tion, and usually exhibiting the external larger ribs : the
sides of the slit are thickened, and the outside groove is
represented by a white ridge. L. 0-45. B. 0-35.

Var. 1. subdepressa. Somewhat larger, more depressed,
and expanded at the sides.

Var. 2. data. Also larger than usual, much higher, and
more solid.

Yar. 3. incurva. Smaller, more raised, and compressed at
the sides, with the beak almost overhanging the posterior
margin ; sometimes of a pinkish colour inside.

Habitat : Everywhere on shells and stones, from
low-water mark at spring tides to 90 f. ; off the Mull of
Galloway, in 110-145 f. (Beechey) . Var. 1. Shetland, in
deep water. Var. 2. Fishguard, and Larne near Belfast
(J. G. J.). This variety also occurs in the Red Crag;
it is nearly as high as long. Var. 3. Oban, Skye, and
Shetland (Barlee and J. G. J.). E.fissura is fossil in
Ireland, according to Mr. James Smith ; and it is rather
common in the Red and Coralline Crag ; Antwerp ter-
tiaries (Nyst) ; Christiania, in the newer glacial forma-
tion, 150-200 ft. (Sars) . Living in the North Atlantic,
from Finmark and the Faroe Isles to the Canaries (where

EMARGINULA. 261

Mr. M f Andrew noticed that it decreased in size), at
various depths between 1 and 80 f.

Curious old Petiver called this shell the " cracked
Barnstaple Limpet/' in consequence of Lister having
figured it as found in that place. According to De
Gerville it bears the name of " Tentaille " in the north
of France. The inside is sometimes greenish or rose-
colour, being probably stained by algse or nullipores.

The first locality given by Linne for Patella fissura
is England, on Lister's authority ; his description an-
swers to the present species, as well as to E. rosea. It
is the E. reticulata of J. Sowerby, who however does
not say that it is distinct from E. fissura, but gave
it a new name because of the then prevalent opinion
that no fossil was the same as any recent species : his
reflection on the subject is somewhat hazy, though
pious. It is also the E. conica of Sars (but not of
Schumacher), E. Miilleri of Forbes, E. leevis and E.
fissurata of Recluz, whose E. tenuis appears to be the
young.

2. E. ro'sea*, Bell.

E. rosea, Bell, in Zool. Journ. i. p. 52, pi. 4. f. 1 ; F. & H. ii. p. 479,
pi. lxiii. f. 3.

Body white : mantle not projecting beyond the shell, and
having a scalloped margin ; it is notched in front to form the
tubular fold, which is bordered on each side by an angulated
prominent lobe : tentacles of moderate length, and stout : eyes
rather large, placed on distinct, although short, pedicles or
stalks : foot large, strong, and very steep-sided. At its junc-
tion with the rest of the body is a circle of about 20 very
short papillary cirri (F. & H.).

Shell smaller and much narrower than E. fissura, and
otherwise distinguishable in the following particulars : — it is
proportionally broader in front than behind, and pinched up

* Rosecoloured.

262 FISSURELLIDiE.

at the sides ; the front is more arched or convex, and the back
more concave ; the longitudinal ribs are more closely set, and
mostly equal- sized; the cancellation is smaller, and exhibits
round holes instead of square lattice-work ; the colour is
often pinkish ; the beak quite overhangs the front margin in
full-grown specimens, and it is invariably longer, and greatly
incurved ; the slit is much shorter ; the mouth is smaller ;
and the inside is frequently reddish-brown, and the cancelli
are marked by white spots. L. 0*225. B. 0-185.

Habitat : Common in 7-25 f. on the coast of Dorset
(Bell and others); Exmouth (Clark); Plymouth (J.G.J.);
Cornwall (Peach and others) ; Scilly Isles (Lord Vernon) ;
Channel Isles (Hanley and others) . Coralline Crag at
Sutton (coll. S. Wood); Palermo (Philippi). Its extra-
British distribution in a recent state is entirely southern,
but extensive; it embraces the coasts of France, Italy,
Algeria, and the Hellespont, at depths varying from
8 to 95 f.

I have taken this living with E. fissura ; other-
wise I should have been disposed to consider it an
aberrant form of that species. Mr. Alder lately com-
pared the tongue of E. rosea with a drawing which he
had previously made of the same organ in E. fissura ;
and he notices the following small points of difference.
u The uncini or lateral spines are of three kinds. The
large inner one appears to be longer and more produced
at the point than in E. reticulata [E. fissura] ; and the
spines of the second kind, which are denticulated at the
points, are four in number in E. rosea, while (if my
drawing is correct) there are only three in E. reticulata
[E. fissura] . Their tips appear to be more slender."
The present species must be very prolific, judging from
the extraordinary number of the ova produced in April ;
each is enclosed in a cartilaginous case. Specimens of
a larger size than usual are only 3| lines long. Their

EMARGINULA. 263

height often exceeds the breadth. Those from the
Mediterranean are mnch smaller than oivrs. The late
Chevalier Verany found one in the stomach of a flamingo
that was killed in the neighbourhood of Nice.

It is the E. conica of Schumacher and Risso ; but
the description given by the former is generic only, and
that by the latter is (as usual) almost enigmatical.
Lamarck's E. rubra is probably also the same species.
The Mediterranean or dwarf form is E.pileolus, Michaud,
E. capuliformis , Philippi, E. curvirostris, Deshayes, and
E. Costce, Tiberi. We have here a goodly choice of
specific names. I would have adopted the first and
earliest (conica) , if any modern conchologist of repute
had set the example ; it is besides more characteristic
and appropriate than rosea. Montagu must have known
the present shell, but considered it a variety of E. fissara ;
he sent a specimen with the latter specific name to Mr.
Dillwyn.

3. E. crassa*", J. Sowerby.

E. crassa, Sow. Min. Conch, p. 73, t. 33, upper figures ; F. & H. ii. p. 481,
pi. lxiii. f. 2, and (animal) pi. C C. f. 2.

Body white : mantle rather thick at its edge : tentacles thick
and cylindrical: eyes apparently smaller in proportion than
those of our other species : foot having narrow sides, which, at
their junction with the rest of the body, are studded with
about 30 short somewhat unequal cirri (Alder).

Shell usually more depressed than that of cither of the two
former species, moderately solid, opaque, slightly glossy :
sculpture, 40-50 broad and compressed longitudinal ribs (each
of which is sometimes divided into three), with as many
smaller intermediate ones ; all these ribs are crossed by fine,
equally numerous, and wavy concentric striae or wrinkles, pro-
ducing a delicately granulated appearance ; the surface is like-
wise covered with minute white glistening dots arranged in
longitudinal rows : colour white : beak small and somewhat

* Solid.

264 FISSURELLIDiE.

angular, usually less excentric than in the other species ; it is
twisted a little to the left, and forms a spire of between one and
two whorls : slit rather narrower above than below, extending
(in adult specimens) from the middle of the front margin
between one-fourth and one-fifth of the way up, being closed
in the line of its previous passage, and becoming a rather
broad and shallow groove which is closely laminated trans-
versely : mouth varying in shape from oval to roundish -oval,
delicately scalloped and notched by the impression of the ribs :
hiside porcelain-white and nacreous, exquisitely and closely
but irregularly lineated in a concentric direction ; the edges
of the slit and groove are thickened. L. 1.25. B. 1.

Habitat : West coast of Scotland, and Shetland, in
20-75 f. (J. G. J., Barlee, and others); " at Oban it is
found alive nnder loose stones, which are uncovered at the
fall of high spring-tides, as well as by dredging ; the tide
sometimes retreats fourteen feet " (Bedford) ; co. Antrim,
off the Copeland Isles, in 20-60 f. (Hyndman) ; Dublin
coast (Thompson). Red and Coralline Crag (Wood) ;
Opslo, near Christiania (Lyell); Belgian tertiaries (Nyst);
Lamato, in Calabria (Philippi). The correctness of this
last locality in some measure depends on the probabi-
lity of E. crassa being identical with E. decussata of
Philippi. Its foreign distribution, as a recent species,
is entirely Scandinavian. Loven, Malm, M f Andrew
and Barrett, Asbjornsen, and Koren have dredged it at
different points between Bohuslan and Drontheim, in
from 10 to 60 f.

This noble shell is never likely to become common in
collections, until some plan is discovered for dredging
in rocky ground. The young differs from E. fissura
of the same size in being more depressed, and in its
peculiar sculpture. In that species the ribs are strong,
and the surface is coarsely cancellated ; in this the ribs
are fine and more numerous, and the surface is delicately
granulated. The rows of small white dots are always

FISSURELLA. 265

visible in E. crassa ; and the slit is shorter relatively to
the size of the shell.

Genus III. FISSUREL'LA*, Bruguiere. PL VI. f. 4.

Body senrioval : mantle protruded in front through a hole or
slit in the crown of the shell : foot covered with papilla?.

Shell ovately conical, perforated on the anterior side of the
crown : beak spiral in the young only : inside thickened around
the terminal perforation.

This is one of the genera of mollusks which Cuvier
illustrated in his celebrated Memoires on their ana-
tomv. He considered it to be allied to Haliotis. Al-
though the animal in its normal state extends beyond
the shell, it can be entirely withdrawn into it, like
Vitrina. Woodward has well remarked that its organi-
zation has certain homological affinities with that of the
Lamellibranchiate bivalves, in the number and position
of the gills, as well as in the pallial tube. According to
Beudant, it is equally incapable with Capulus of existing
in fresh water. The opening in the summit of the shell
resembles a keyhole ; in the young it is placed on the
anterior side of the beak, which is distinctly spiral at
that period of growth. The fry might be mistaken for
that of Puncturella, if it had also an internal sheath
or process. Fissurella is represented in all seas, scantily
in the North Atlantic, but amply in southern latitudes,
whence many fine and gaily painted species have been
brought by collectors. The number of genera into
which this has been divided by Gray and other English
conchologists was noticed by Philippi as one of the
curiosities of science.

* Having a small cleft in the shell,
VOL. III. X

266 FISSURELLID.E.

Fissurella Gr^eca"*, Linne.

Patella grceca, Linn. S. N. p. 1262. F. reticulata, F. & H. ii. p. 469,
pi. Isiii. f. 4, 5, and (animal) pi. B B. f. 7.

Body cream colour or yellowish, passing into deep orange :
mantle ample, extending beyond the sides of the shell, and
expanded over the head as a hood or veil ; margin fringed with
a row of very small and short but stout cirri, which correspond
with the longitudinal ribs of the shell : head tumid and strong :
tentacles extensile : eyes black and rather small : gills very
thick, brownish : foot yellowish, dilated, with broad sides ;
the upper part is studded with a row of from 30 to 40 pa-
pillae, which are usually by turns larger and smaller.

Shell forming a cone of variable height, small and appa-
rently stunted specimens being more raised than younger ones
of a regular growth ; it is solid, opaque, nearly lustreless :
sculpture, generally about 25 strong and cord-like, but not
much raised, longitudinal ribs, and an equal number of smaller
intermediate ones ; all these are crossed by about 30 narrower
and imbricated concentric ribs, which by the decussation
make the crests of the other ribs nodulous or vaulted ; the
surface of living, and especially immature specimens is covered
with microscopical longitudinal striae ; in the fry are observ-
able a few white dots, arranged in lines as in Puncturella and
Emargbiula : colour pale yellowish- white with a few broad
rays of reddish-, greenish-, or dark-brown,which are sometimes
intermingled or variegated : beak very small, only persistent
in the young, inflected and twisted a very little to the left,
and forming a spire of between one and two whorls : slit oblong,
broader above than below, contracted at the outer sides, which
project in the middle like the teeth of a saw: mouth oval,
finely scalloped by the ribs and toothed within ; these teeth
are often double ; when the shell is placed on its base, the
outline of the mouth is more or less arched on each side, and
resembles the sole of a human foot: inside porcellanous, ex-
hibiting the coloured rays in young specimens ; it is delicately
lineated around the margin, as in the interior of all shells
belonging to other genera of the same family: pallial scar
wide and irregular, having a large central impression analogous
to that of Patella. L. 1-25. B. 0-75.

* Inhabiting the Archipelago.

FISSURELLA. 267

Habitat : South-e astern , southern, and western coasts
of England (including- the Channel Isles), Bristol Chan-
nel, Isle of Man, Angiesea, all around Ireland, and the
west of Scotland ; not uncommon in oyster beds and
on old shells and rocks, from low-water mark to 50 f. :
Caithness coast (Gordon); Orkneys (Thomas); and
Forbes gives it, in his report to the British Association
for 1850, as living at 10 f. in Shetland. It occurs fossil
at Moel Tryfaen (Darbishire); Bed and Coralline Crag
(S. Wood) ; as well as in the Belgian, French, and Italian
tertiaries. South of Great Britain it has a wide distri-
bution in a recent state, as far as the iEgean and
Canaries, at depths ranging from the shore-line to 95 f.
I am not aware of any northern locality.

Petiver called this the " thimble limpet," possibly
from its being open at the top, like a tailor's thimble.
The number of longitudinal ribs, and consequent com-
pactness of the cancellation, vary greatly; in a specimen
from Guernsey I counted no less than seventy-two of
these ribs.

The only habitat assigned by Linne to his Patella
grceca was the Mediterranean. His description, al-
though short, suits our shell ; and his references, with
the exception of Adanson (and perhaps also of Gualtieri
and Begenfuss), are quite appropriate. Our shell is the
P. larva, reticulata (in the index P. reticulata) of Da
Costa, F. cancellata, Gray (but not of G. B. Sowerby),
F. Europaa, Sowerby, F. occitanica, Becluz, and F. Lis-
ten, Woodward ; the fry is P. apertura, Montagu, Sipho
radiata, Brown, F. striata, Becluz, and Cemoria Monta-
guana, Leach.

I have a worn specimen of F. nubecula, Linne, in
Turtoms collection, which, he states (in his c Concho-
logical Dictionary ') , had been dredged off the Land's

n 2

268 CAPULID.E.

End. Couch gives the same habitat ; and Peach noticed
this species as found by him at Gorran, in Cornwall ; but
he appears to have mistaken for it the young of F. Grceca.
Better evidence is wanting of F nubecula being British ;
it is not uncommon in the Mediterranean. This is the
F. nimbosa, afterwards F. rosea, of Philippi (but appa-
rently neither of Lamarck's species bearing these names) ,
and F. Philippii of Requiem

Family III. CAPU'LID^E, Fleming.

Body conical or cap-shaped : mantle entire : head snout-
like, furnished with jaws and a stout spinous tongue : tentacles
awl-shaped, widely separated : eyes placed on slight bulgings
or tubercles, about halfway up the tentacles at their outer
bases : gills forming a single plume or row of slender elongated
leaflets, and seated in a large cavity behind the head : foot
fleshy and rounded.

Suell cap-shaped and tumid : epidermis velvety : beak
spiral, turned towards the posterior side, curling downwards,
and twisted to the left : mouth round or transversely oval, with
an irregularly sinuated margin.

The beak or apex of the shell is turned to the rear
and always spiral, as in the last family ; in the Patellidce
it is turned to the front, and only spiral or curved in the
very young state. In Gray's system the present family
and the next are arranged in a different group from that
which contains the Patellidce, and the latter family is
separated by Dentalium from the Fissurellida?.

Genus CA'PULUS* De Montfort. PI. VI. f. 5.

Generic characters the same as those of the family.

These mollusks adhere to stones and old shells in the
coralline and deep-water zones. They probably never

* A receptacle.

capulus. 269

willingly change their places of abode, bnt subsist on
animal or vegetable food brought by marine currents
within reach of their extensile snouts. The female
carries her egg-cases under the neck in front of the foot
until the fry are hatched. According to Loven the
dental apparatus is nearly the same in C. Hungaricus
and Calyptrcea Chinensis ; so that these genera must be
closely allied. But the internal appendage in Calyptr&a
and other genera belonging to the same family indicates
a peculiar structure of the animal which is wanting in
Capulus.

D'Argenville called it Cabochon. It is the genus
Mitra Hungarica of Klein, and Pileopsis of Lamarck.
About a dozen other synonyms have been cited by
Herrmannsen.

Capulus Hungaricus"*, Linne.

Patella ungarica, Linn. S. N. p. 1259. Pileopsis Hungaricus. F. & H.
p. 459, pi. lx. f. 1, 2 (as C. Hungaricus), and (animal) pi. C C. f. 3.

Body whitish, with a yellowish or brown tint : mantle either
the same colour as the rest of the body, and thickly covered
with minute milk-white specks, or else pinkish-white or red
with a border of bright yellow or orange ; margin thickened,
and fringed with fine filaments : head broad and thick, with
produced lips so as to make the extremity of the muzzle appear
cloven : tentacles variable in length, sometimes of a white or
yellowish colour : eyes small : foot bordered in front by a
puckered ruff or membrane.

Shell not unlike a cornucopia, or an ancient fool's or
jester's cap, with a roundish base, the height of the cone
depending on the comparative dilatation of this latter part ; it is
rather thin, semitransparent, and of a dull hue beneath the
epidermis : sculpture, numerous fine ribs which radiate from
the beak towards the margin, near which they almost disap-
pear, besides very slight and close-set minute transverse striae
between the ribs ; marks of growth conspicuous but irregular :

* Hungarian.

270 CAPULIDiE.

colour varying from pale yellowish -white to dull reddish-
brown, rarely milk-white : epidermis arranged in concentric
layers, which are often fringed by a row of leaf-like or tri-
angular points ; it is easily rubbed off, and seldom remains on
the upper part: beak in adult specimens overhanging the
posterior side, and gradually becoming spiral with from two
to three whorls, which are placed sideways, and separated by
a distinct and rather deep suture : mouth extremely open, in
consequence of the expansion of the base : inside lustrous,
either porcelain-white or having a rosy and sometimes lovely
pink tinge ; it is concentrically and microscopically lineated
from the middle to within a short distance of the margin (as
in the Fissurellidce); and the border of the margin is marked
lengthwise with longitudinal lines, which run at a right angle
to the other set of lines ; margin in young specimens finely
notched or scalloped : muscular scar horseshoe-shaped, with the
opening in front and the broad ends on each side of the neck.
L. 1-5. B. 1-75.

Habitat : Attached to rocks and large shells, and
especially frequenting oyster- and scallop -be