slightly gaping; hinge with one or two cardinal teeth, and a narrow
groove for the internal ligament; ligament double, the external one
short, the internal one fixed in the internal grooves. The two ligaments
distinguish this genus from all other bivalves. Inhabits the West Indian
and American seas. Forty-five species.
Amphidesma variegatum.
A. donacillum.
A. lacteum.
A. corneum.
A. albellum.
A. flexuosum.
A. prismaticum.
A. phaseolinum.
A. Tenuii.
A. purpurescens.
A. nucleolum.
A. physioides.
A. pulchrum.
A. pallidum.
A. formosum.
A. roseum.
A. corbuloides.
A. glabrellum.
A. lucinale.
A. Boysii.
A. lenticulare.
A. cancellatum.
A. reticulatum.
A. duplicatum.
A. læve.
A. prismaticum.
A. ellipticum.
A. subtruncatum.
A. solidum.
A. cordiforme.
A. rupium.
A. lamellosum.
A. crenulatum.
A. punctatum.
A. multicostatum.
A. siculum.
· · · · ·
A. transversum.*
A. rubro-lineata.*
A. decisa.*
A. bellastriata.*
A. orbiculata.*
A. equalis.*
A. punctata.*
A. radiata.*
A. lepida.*
FAMILY VI.
CORBULACEA. Two genera.
1. Genus _Corbula_. Pl. VI.
_Animal._ Unknown.
_Shell._ Tolerably solid, regular, inequivalve, inequilateral with a
conical, flexed, ascending, primary tooth in each valve; a cavity at the
side; no lateral teeth; ligament interior, placed in the cavities; two
neighbouring muscular impressions. Inhabits the British and American
seas. Ten species. Four fossil.
Corbula Australis.
C. sulcata.
C. erythrodon.
C. ovalina.
C. semen.
C. Taitensis.
C. nucleus.
C. impressa.
C. porcina.
· · · · ·
C. contracta.*
2. Genus _Pandora_. Pl. VI.
_Animal._ Body much compressed, somewhat elongated, in form of a furrow,
in consequence of the union of the edges of the mantle, and its
continuation with the tubes, which are united and short; foot small,
thickest in front, and issuing through a tolerably large cleft in the
mantle.
_Shell._ Regular, white, elongated, much compressed, inequivalved,
inequilateral; right or upper valve quite flat, with a fold; summits
feebly marked; hinge anomalous, formed by a transverse cardinal tooth on
the right; valve entering a corresponding cavity in the left; ligament
internal, oblique, triangular, inserted in a somewhat deep pit, with
edges a little projecting on each valve; two round muscular impressions.
Inhabits the Mediterranean, British, and American seas. Four living
species, and two fossils, according to Defrance.
Pandora rostrata.
P. obtusa.
· · · · ·
P. trilineata.*
P. punctata.*
FAMILY VII.
LITHOPHAGA. Three genera.
1. Genus _Saxicava_. Pl. VI.
_Animal._ Long, subcylindrical, the mantle closed in all parts,
prolonged behind by two long tubes, thick and close together externally,
pierced interiorly and in front with a round orifice, for the passage of
a very small foot; mouth very large; labial appendages small; branchial
laminæ free, the external pair much shorter than the internal.
Lamarck has thought proper to remove this genus from the Mytilus; it
possesses the faculty, like the Pholas, of penetrating rocks and
substances, and cannot be extracted but by breaking the substance in
which it is imbedded.
_Shell._ Thick, with an epidermis, a little irregular, elongated,
subcylindrical, obtuse at both ends; summits feebly marked; hinge
toothless, or with a very small rudimentary tooth; ligament external,
somewhat inflated; two round muscular impressions distinct, and several
others irregular. Inhabits the British and American seas, in cavities,
which they bore in rocks or wood. Nine species.
Saxicava rugosa.
S. gallicana.
S. veneriformis.
S. pholadis.
S. Australis.
· · · · ·
S. distorta.*
S. rhomboides.*
S. carditoides.*
S. californica.*
2. Genus _Petricola_. Pl. VII.
_Animal._ Unknown.
_Shell._ Subtrigonal, more or less irregular, transverse, inequilateral;
upper side narrowed and a little gaping; lower side rounded; hinge with
two teeth in each valve, or in one valve only. Inhabits the Australian
seas, boring into wood and rocks. Thirteen species.
Petricola lamellosa.
P. Ochrolenca.
P. Semilamellata.
P. lucinalis.
P. striata.
P. costellata.
P. recellaria.
P. exilis.
P. ruperella.
P. chamoides.
P. pholadiformis.
P. labagella.
P. linguatula.
3. Genus _Venerirupis_. Pl. VII.
_Animal._ Unknown, but probably resembling the Venus.
Another lithophagous shell, taken from the genus Venus, and
distinguished from it by the different disposition of the teeth.
_Shell._ Transverse, inequilateral, posterior side short, the anterior
gaping slightly. Hinge with two teeth on the right valve, three on the
left, and sometimes three on both—these are small, near together, and
parallel. Ligament exterior. Inhabits the British seas, boring into
rocks and clay. Eight species.
Venerirupis perforans.
V. nuclea.
V. Ira.
V. corditoides.
V. exotica.
V. distans.
V. crenata.
V. alata.
FAMILY VIII.
NYMPHACEA. Ten Genera.
This family is divided into N. Solenaria and N. Tellinaria, from their
resemblance to the Solen and Tellina.
N. SOLENARIA. Three genera.
1. Genus _Sanguinolaria_. Pl. VII.
_Animal._ Unknown.
_Shell._ Oval, compressed, a little elongated, gaping but little,
equivalve, subequilateral, rounded at both extremities; no mark of
posterior keel; summits feebly marked; hinge formed by one or two
contiguous cardinal teeth upon each valve; ligament projecting, two
round muscular impressions, distant and joined by a narrow palleal
impression strongly sinuous behind. Inhabits the sea at Jamaica and
shores of America. Nine species.
Sanguinolaria occidens.
S. rosea.
S. alba.
S. livida.
S. rugosa.
· · · · ·
S. fusca.*
S. lusoria.*
S. Nuttallii.*
S. Californiana.*
2. Genus _Psammobia_. Pl. VII.
_Animal._ Unknown.
Resembling the Tellina, from which it was taken, but not having an
irregular plait on the anterior part.
_Shell._ Transverse, oblong-ovate, or elliptical, flattened, slightly
gaping at one side; summits projecting; hinge formed by two primary
teeth in the left valve, and one in the opposite one Inhabits the
European and American seas. Twenty-one species.
Psammobia virgata.
P. ferroensis.
P. vespertina.
P. muculosa.
P. alba.
P. Cayennensis.
P. lævigata.
P. Tellinella.
P. cærulescens.
P. elongata.
P. flavicans.
P. squamosa.
P. pulchella.
P. aurantia.
P. fragilis.
P. livida.
P. galathea.
· · · · ·
P. lusoria.*
P. fusca.*
P. Pacifica.*
P. Florida.*
3. Genus _Psammotæa_. Pl. VII.
_Animal._ Unknown.
_Shell._ Of the same form as the Psammobia, but differing in the number
of teeth, the left valve of the Psammotæa having only one tooth; and
sometimes one valve is without teeth, while the other has two; ligament
exterior, attached to callosities at the hinge, and without an irregular
plait. Inhabits the Australian seas. Seven species. One fossil species.
Psammotæa violacea.
P. zonalis.
P. pellucida.
P. candida.
P. tarentina.
P. donacina.
P. serotina.
N. TELLINARIA. Seven Genera.
The two last of these genera have no lateral teeth, the rest have one or
two.
4. Genus _Tellina_. Pl. VII.
_Animal._ Body triangular, much compressed: the free edge of the mantle
furnished with a row of tentacular, largest and longest in the rear;
foot very large, compressed and pointed to the front; buccal appendages
nearly as large as the bronchial laminæ, of which the external pair are
much smaller than the internal; the anterior contractile muscle larger
than the other; tubes very distinct.
_Shell._ Of a somewhat variable form, generally striated longitudinally
and much compressed, equivalved, more or less inequilateral; the
anterior side almost always longer and more rounded than the posterior,
which constantly presents a flexuous fold, at least at its inferior
edge; summits feebly marked; hinge similar; one or two cardinal teeth;
two lateral teeth, far apart with a pit at their base in each valve;
ligament posterior, large; round muscular impressions. The finest
species of this beautiful shell are found in the pearl fisheries of
Ceylon; and numerous species on the American shore. Sixty-eight species.
Tellina unimaculata.
T. virgata.
T. semizonalis.
T. staurella.
T. lutirostra.
T. rostrata.
T. Spengleri.
T. radiata.
T. crucigera.
T. elliptica.
T. albinella.
T. rosea.
T. foliacea.
T. operculata.
T. chloraleuca.
T. remies.
T. sulcata.
T. crassa.
T. exilis.
T. donacina.
T. nitida.
T. striatula.
T. decussata.
T. obliqua.
T. nymphalis.
T. capsoides.
T. seradiata.
T. margaritina.
T. strigosa.
T. planata.
T. depressa.
T. pulchella.
T. fabula.
T. tenuis.
T. sulphurea.
T. cornuta.
T. iris.
T. levigata.
T. linguafelis.
T. rugosa.
T. lacunosa.
T. gargadia.
T. pristis.
T. gigas.
T. scalaris.
T. psammotella.
T. scobinata.
T. Brasiliana.
T. umbonella.
T. deltoidalis.
T. multangula.
T. solidula.
T. polygona.
· · · · ·
T. ostracea.*
T. intastriata.*
T. polita.*
T. tenera.*
T. flexuosa.*
T. secta.*
T. decorate.*
T. lateralis.*
T. alternata.*
T. vimaculata.*
T. pumicea.*
T. alta.*
T. nasuta.*
T. lineata.*
T. sordida.*
5. Genus _Tellinides_. Pl. VII.
_Animal._ As above.
This genus is very nearly allied to the Psammobia, Tellina, and Lucina,
but upon close examination it will be found to be distinct from either.
_Shell._ Equilateral, transverse, somewhat elongated, nearly without the
flexuous plait; two divergent cardinal teeth, of which the anterior is
but little distant from the summit. Inhabits the Bay of Naples. Two
species. One species is found on the shores of America.
Tellinides Timorensis.
· · · · ·
T. rosea.*
6. Genus _Corbis_. Pl. VII.
_Animal._ Differing slightly from the Lucina.
This genus was classed by Lamarck with the Lucina, but the great
difference in the organization of the animals discovered by Cuvier, has
made this a distinct genus.
_Shell._ Equivalve, transverse, without any irregular fold on the
anterior margin, having the beaks flexed inward and opposite; two
cardinal teeth; two lateral, the posterior of which is nearest the
hinge; muscular impressions simple, ligament external. Inhabits the
Indian Ocean.
Corbis fimbriata.
C. maculata.
7. Genus _Lucina_. Pl. VII.
_Animal._ Very imperfectly known.
_Shell._ Inequilateral, suborbicular, beaks small, pointed, and oblique;
two divergent cardinal teeth, one of which is bifid, and which vary or
disappear with age; two lateral teeth sometimes obsolete, the posterior
approaches nearest to the cardinal teeth; two muscular impressions far
apart, the posterior in shape of a band, sometimes very long; ligament
external. Inhabits the British and American seas. Twenty-six species.
Lucina Jamaicensis.
L. edentula.
L. radula.
L. lactea.
L. circinaria.
L. columbella.
L. mutabilis.
L. squamosa.
L. Peruviana.
L. fimbriata.
L. undata.
L. divaricata.
L. scabra.
L. sinuata.
L. lutea.
L. globularis.
L. digitalis.
L. Pecten.
L. reticulata.
L. carmaria.
L. concentrica.
· · · · ·
L. bella.*
L. Pennsylvania.*
L. sphæroides.*
L. Californica.*
L. Nuttallii.*
8. Genus _Donax_. Pl. VII.
_Animal._ As in Tellina.
_Shell._ Transverse, inequilateral, equivalve; anterior side short and
obtuse; two primary teeth in one or both valves; one or two lateral
teeth varying in distance; two round muscular impressions; ligament,
external, short, and inserted at the posterior impression. Inhabits the
seas of Europe and America. Thirty-one species.
Donax pubescens.
D. cuneata.
D. radians.
D. abbreviata.
D. ringens.
D. Cayennensis.
D. denticulata.
D. cinatina.
D. cardioides.
D. scorta.
D. compressa.
D. columbella.
D. Australis.
D. bicolor.
D. merois.
D. scripta.
D. trunculata.
D. fiabagella.
D. Martiniænsis.
D. triquetra.
D. rugosa.
D. elongata.
D. deltoides.
D. veneriformis.
D. Vittata.
D. granosa.
D. epidermia.
D. minima.
· · · · ·
D. variabilis.*
D. fossar.*
D. Californica.*
9. Genus _Capsa_. Pl. VII.
_Animal._ As above.
_Shell._ Transverse, equivalve, valves approximate and close; three
primary teeth in the right valve, and a single bifid tooth in the left,
inserted into a cavity in the opposite one; no lateral teeth; ligament
external and on the short side, as in Donax, from which it was separated
by Lamarck, on account of the peculiarity of the hinge, inhabits the
Indian Ocean. Three species.
Capsa levigata.
C. Braziliensis.
C. Donaoides.
10. Genus _Crassina_. Pl. VII.
_Animal._ As above.
_Shell._ Distinguished from the Venus by having only two teeth on each
valve, and from the crasatella by the position of the ligament; solid,
suborbicular, thick, hinge with two strong diverging primary teeth in
the right valve, and two unequal ones on the other; ligament external.
Inhabits the Scottish and Devonshire coasts. One species.
Crassina Danmoniensis.
FAMILY IX.
CONCHACEA. Seven Genera.
This family is divided into _Conchæ Marinæ_, and _Conchæ Fluviatiles_.
CONCHÆ MARINÆ. Four Genera.
1. _Cyprina._ Pl. VII.
_Animal._ Thick, oval, foot compressed, falciform, geniculated mantle
closed behind, and pierced by two oval apertures with cirrous edges: no
veritable tubes.
_Shell._ With epidermis; thick, regular, substriated longitudinally,
sub-cordiform, equivalved, inequilateral; summits strongly flexed to the
front and often contiguous; hinge thick, subsimilar, formed by three
slightly converging cardinal teeth, and by a posterior lateral tooth,
sometimes obsolete; ligament very thick; muscular impressions distant,
subcircular, and united by a narrow marginal band. Inhabits the Atlantic
Ocean and British seas. Two living species. Seven fossil.
Cyprina tennistria.
C. Icelandica.
2. Genus _Cytherea_. Pl. VII.
_Animal._ Oval or round, generally but little compressed; edges of the
mantle undulous, and garnished with tentacular cirri in one row; foot
considerable, compressed, trenchant, in other respects diversiform;
tubes tolerably elongated, and most usually united; mouth small; labial
appendages quite small; branchiæ wide, short, free, or not united either
with one another or with those of the opposite side.
_Shell._ Solid, equivalve, regular, inequilateral; summits equal,
reflexed, and slightly projecting; four primary teeth on one valve, of
which three are divergent, and approximating at the base, and one
remote—this circumstance easily distinguishing it from the Venus. On the
other valve are three primary divergent teeth with a distant cavity
parallel with the edge. Inhabits the British, Mediterranean, and
American seas. Eighty-three living species. Nine fossil.
Cytherea petechialis.
C. morphina.
C. Castanea.
C. casta.
C. lusoria.
C. graphica.
C. impudica.
C. purpurata.
C. zonaria.
C. tigrina.
C. pulicaris.
C. numulina.
C. abbreviata.
C. pectinata.
C. flexuosa.
C. ranella.
C. lunularis.
C. divaricata.
C. corbicula.
C. meretrix.
C. tripla.
C. erycina.
C. impar.
C. Guiniensis.
C. pectoralis.
C. Arabica.
C. Florida.
C. immaculata.
C. Chione.
C. hepatica.
C. citrina.
C. lactea.
C. lata.
C. lincta.
C. trigonella.
C. prostrata.
C. Hebræa.
C. tigerina.
C. ornata.
C. umbonella.
C. castrensis.
C. picta.
C. scripta.
C. mixta.
C. muscaria.
C. plicatina.
C. dentaria.
C. nodulosa.
C. cuneata.
C. lunaris.
C. placunella.
C. cygnus.
C. juvenilis.
C. gigantea.
C. Venetiana.
C. lilacina.
C. rufa.
C. erycinella.
C. Dione.
C. planatella.
C. trimaculata.
C. nitidula.
C. pellucida.
C. maculata.
C. lucinalis.
C. albina.
C. exoleta.
C. mactroides.
C. concentrica.
C. sulcatina.
C. interrupta.
C. punctata.
C. undatina.
C. gibbia.
C. macrodon.
C. testudinalis.
C. rugifera.
C. aspergata.
C. squamosa.
C. cardilla.
· · · · ·
C. occulta.*
C. callosa.*
C. crassatelloides.*
3. Genus _Venus_. Pl. VII.
_Animal._ As above.
_Shell._ Solid, thick, regular, perfectly equivalved and close, more or
less inequilateral; summits well marked and inclined to the front; hinge
subsimilar; the middle cardinal tooth forked, or three cardinal teeth
more or less contiguous and convergent towards the summits; ligament
thick, often arcuated, convex, exterior; two distant muscular
impressions; cordiform depressions beneath the beaks. Inhabits the
British and American seas. One hundred living species. Nine fossil.
Venus reticulata.
V. rugosa.
V. corbis.
V. crebiscula.
V. discina.
V. cancellata.
V. marica.
V. sulcaria.
V. cardivides.
V. texturata.
V. elliptica.
V. rariflamma.
V. mercenaria.
V. pullastra.
V. gallina.
V. truncata.
V. pectinula.
V. anomala.
V. lamellata.
V. exilis.
V. rufa.
V. Scotica.
V. hiantina.
V. virginea.
V. corugata.
V. ovulæa.
V. papilionacea.
V. callipyga.
V. punctifera
V. nebulosa
V. literata
Venus floridella.
V. aphrodina.
V. pulchella.
V. aphrodinoides.
V. tristis.
V. flammea.
V. puerpera.
V. verrucosa.
V. pygmæa.
V. casina.
V. crenulata.
V. plicata.
V. granulata.
V. pectorina.
V. cingulata.
V. textilis.
V. grisea.
V. geographica.
V. Dombeii.
V. decussata.
V. lagopus.
V. glandina.
V. gallinula.
V. retifera.
V. sulcata.
V. galactites.
V. exalbida.
V. scalarina.
V. dorsata.
V. aurea.
V. crassisulca.
V. carneola.
V. petalina.
V. cornularis.
V. adspersa.
V. opima.
V. turgida.
V. flammiculata.
V. strigosa.
V. Perronii.
V. elegantina.
V. undulosa.
V. vermiculosa.
V. vulvina.
V. marmorata.
V. Malabarica.
V. laterisulca.
V. subrostrata.
V. phaseolina.
V. Florida.
V. bicolor.
V. catenifera.
V. sinuosa.
V. rimularis.
V. ovata.
V. pumila.
V. inquinata.
· · · · ·
V. notata.*
V. præparea.*
V. elevata.*
V. inequalis.*
V. castanea.*
V. Nuttallii*
V. staminea.*
V. Californica.*
V. lamellifera.*
V. Mortoni.*
4. Genus _Venericardia_. Pl. VII.
_Animal._ Nearly as above.
_Shell._ Suborbicular, inequilateral, equivalve, sides having usually
longitudinally rayed ribs; hinge with two oblique cardinal teeth in each
valve, turned in the same direction. Five living species. Ten fossil
species.
Venericardia Australis.
V. imbricata.
V. flammea.
V. Tankervillii.
V. crassicosta.
CONCHÆ FLUVIATILES. Three Genera.
5. Genus _Cyclas_. Pl. VII.
_Animal._ Body oval, thick; edges of the mantle simple; tubes short and
united; foot wide, compressed at base, and terminated by a sort of leg
or appendage.
The shells of this genus are very small, found buried in the mud of
fresh waters; summits never eroded, but some species are so thin as to
be transparent.
_Shell._ With an epidermis, oval, or suborbicular, regular, equivalved,
inequilateral; summits obtuse, contiguous or turned anteriorly; hinge
similar, complex, formed by a slightly variable number of cardinal
teeth, and by two separated lateral teeth with a pit at the base;
ligament exterior, posterior, and inflated; two distant muscular
impressions, united by a faintly marked abdominal band, and without
posterior excavation. Fifteen species.
Cyclas cornea.
C. obliqua.
C. obtusalis.
C. Australis.
C. striatina.
C. rivicola.
C. lacustris.
C. calyculata.
C. fontinalis.
C. sulcata.
· · · · ·
C. Sarratogea.*
C. Rhomboidea.*
C. similis.*
C. Partumeia.*
C. dubia.*
6. Genus _Cyrena_. Pl. VII.
_Animal._ As above.
_Shell._ Rounded and trigonal, ventricose, inequilateral; hinge with
three teeth on each valve; two lateral teeth, one of which is near the
primary ones; ligament exterior, situated on the largest side. The
apices are always eroded or carious in shells of this genus. Inhabits
the rivers of China. One is found on the coast of Carolina. Ten living
species. One fossil.
Cyrena orientalis.
C. depressa.
C. fuscata.
C. violacea.
C. Ceylonica.
C. trigonella.
C. cor.
C. fluminea.
C. Bengalensis.
· · · · ·
C. Caroliniensis.*
7. Genus _Galathea_. Pl. VII.
_Animal._ As above.
_Shell._ Equivalve, subtrigonal, covered with a greenish epidermis; the
surface beneath is white, with several violet streaks radiating from the
summit to the margin; two furrowed cardinal teeth upon one valve, three
upon the other, the middle one being largest and callous; muscular
impressions double and lateral. Inhabits the rivers of Ceylon. One
species.
Galathea radiata.
FAMILY X.
CARDIACEA. Five Genera.
1. Genus _Cardium_. Pl. VII.
_Animal._ Body somewhat inflated; mantle edged with tentacular cirri in
all its inferior part; tubes united, of moderate size, and provided with
cirri at the extremity; mouth transverse, very wide, with moderate
labial appendages; foot very large, cylindrical, somewhat inclined
anteriorly; branchiæ thick, rather small, especially the external
laminæ: the internal united in all their extent.
_Shell._ Inflated, equivalve, sub-cordiform (when viewed anteriorly,
usually costated from the apex to the circumference); summits very
evident, but slightly flexed to the front; hinge complex, similar,
formed of two oblique, conical cardinal teeth, and of two distant
lateral teeth, upon each valve; ligament dorsal, posterior and very
short. Inhabits the European and American seas. Fifty-seven living
species. Fourteen fossil.
Cardium indicum.
C. Asiaticum.
C. fimbriatum.
C. aculeatum.
C. tuberculatum.
C. apertum.
C. bullatum.
C. echinatum.
C. biradiatum.
C. pectinatum.
C. isocardium.
C. angulatum.
C. serratum.
C. costatum.
C. ringens.
C. tennicostatum.
C. psudolima.
C. crinaceum.
C. Basilianum.
C. papyraceum.
C. ciliare.
C. levigatum.
C. eolicum.
C. elongatum.
C. rugosum.
C. unedo.
C. medinum.
C. tumotiferum.
C. retusum.
C. rusticum.
C. Greendlandicum.
C. crenulatum.
C. minotum.
C. scobinatum.
C. cardissum.
C. inversum.
C. ventricosum.
C. obtusum.
C. fragum.
C. lineatum.
C. edule.
C. latum.
C. exigunum.
C. rosenum.
C. hemicardium.
C. Junoniæ.
C. muricatum.
C. marmoreum.
C. sulcatum.
C. cifidium.
· · · · ·
C. Mortonii.*
C. substriatum.*
C. Nuttallii.*
C. Californianum.*
C. quadragenarium.*
C. Pennulatum.*
C. pubescens.*
2. Genus _Cardita_. Pl. VII.
_Animal._ Body suborbicular, terminated superiorly by a sort of hook;
mantle but little open; foot terminated at its extremity by a part much
narrower than the base; superior lobes of the branchiæ very short.
_Shell._ Thick, solid, equivalve, more or less inequilateral; summit
dorsal always much flexed anteriorly; hinge similar, formed by two
oblique teeth, one short, cardinal or apicial, the other postapicial,
long, lamellous and arcuated; ligament elongated, subexterior and
inserted; two very distinct muscular impressions, united by a palleal
band, narrow and semicircular. Inhabits the Mediterranean and American
seas. Twenty-three living species. Four fossil.
Cardita Ajar.
C. squamosa.
C. crassicosta.
C. calyculata.
C. nodulosa.
C. trapezia.
C. sulcata.
C. turgida.
C. phrenetica.
C. rufescens.
C. subaspera.
C. intermedia.
C. depressa.
C. sinuata.
C. citrina.
C. orbularis.
C. bicolor.
C. concamerata.
C. aviculina.
C. sublevigata.
C. lithophagella.
· · · · ·
C. borealis.*
C. incrassata.*
3. Genus _Cypricardia_. Pl. VII.
_Animal._ As above.
_Shell._ Obliquely elongated, equivalve, inequilateral; valves striated,
not ribbed; distinguished from the Cardita by having three teeth beneath
the apices, and a callous lengthened tooth or ridge. Inhabits the coast
of Guinea and California. Five living species. Three fossil.
Cypricardia angulata.
C. Guinaica.
C. coralliophaga.
C. rostrata.
· · · · ·
C. Californica.*
4. Genus _Hiatella_. Pl. VII.
_Animal._ Unknown.
_Shell._ Thin, elongated, subrhomboidal, equivalve, very inequilateral,
gaping at its inferior edge, and at its posterior extremity; summit very
anterior, and much flexed to the front; hinge formed of a single tooth
upon one valve corresponding to an emargination in the opposite valve,
or of a small tooth with a cardinal pit upon each valve; ligament
exterior and dorsal. Inhabits the British seas. Two species.
Hiatella Arctica.
H. biaperta.
5. Genus _Isocardia_. Pl. VIII.
_Animal._ Body very thick: edges of the mantle finely papillaceous,
separated inferiorly, and united behind by a transverse band, pierced
with two orifices surrounded with radiating papillæ; foot small,
compressed, trenchant.