158 ASTARTIDA, 
ligament is elongate and narrow ; the posterior muscular scar is nar- 
rower than in the Australian species (Smith.) 
FAMILY—ASTARTID. 
Labial palps plicate, short, triangular. Lobes of mantle disunited in 
their entire length, the branchial margin bearded; gills two pairs, rounded 
in front, tapering and free behind the body. Foot conical, compressed, 
rather angulated behind. Shell thick, triangular or cordiform, oblong, 
generally covered with a brown epidermis; often ornamented with 
concentric striz ; hinge thick, large, and solid. 
Genus, CRASSATELLA—Lamark. 
Mantle entirely open, with the inhalent margins cirrated; palpi 
triangular ; foot compressed, triangular and grooved. Shell solid, closed, 
equivalve, attenuated behind, lunule distinct; hinge composed of two 
sub-diverging, striated primary teeth placed in front of a cartilage pit ; 
lateral teeth usually one in each valve; ligament internal, inserted in a 
pit in each valve. 
C. obesa, Adams, P.Z.S., 1852, p. 90. Shell equivalve, inequi- 
lateral, thick, gibbous, covered with brownish-red, silky epidermis, 
transversely strongly plicated, folds prominent, vanishing towards the 
ventral margin ; lunule impressed, lanceolate ; posterior side sub-pro- 
duced, angled, margin truncated ; anterior side gibbous, margin rounded 
(Adams). 
New Zealand, deep water. (Mr. Strange). 
GC. bellula, Adams, P.Z.S., 1852, ~. 95; Gouldia isabella, Hutton, 
C.M.M., p. 76. Shell ovato-trigonal, sub-equilateral, yellowish-pink, 
immaculate, transversely concentrically plicated, folds obtuse, rather 
crowded, regular, in front undulating and getting smaller (under the lens 
rugulose); posterior side rounded, anterior scarcely truncated ; umbones 
acute, small, approximated (Adams). 
Cook Strait. 
Genus, CARDITA—Lamark. 
Foot sickle-shaped, not byssiferous. Shell equivalve, inequilateral, 
sub-orbicular, generally with radiating ribs; cardinal teeth oblique, 
directed to the same side. 
G. australis, Zamark, Anim. sans vert. vi., p. 383; Quoy and 
Gaimard, l.c., W., p. 480, p7. 78, f. 11-14; G: tridentata, Reeve, Conch. Le., 
f 22. Sub-orbicular, inequilateral, swollen, with about twenty-two 
nodulose radiating ribs, the nodules on the hinder side sub-spinose ; 
lunule cordate, umbones oblique, recurved; margin plicated; pale 
brownish-white ; interior white, more or less marked with rosy or purple. 
Height, 1°5 ; length, 1°75. 
Common. Chatham Islands. Stewart Island. 
