136 TESTACEOUS MOLLUSCA. 
which the lateral ones are crenulated, the central flattened. 1}4.. 13. 
—W. Columbia.—(Like Soleniforme.) 
C. Rinctcutum. Sow. Jun. Z. P. 1840.—C. I. fi 11.— 
Reeve. t. 85. f. 11. Longitudinally oval, small, thin, gaping on 
both sides ; anteriorly elongated, somewhat sparse ;_ the posterior 
ribs narrow and indistinct, the three central ones broad, flattened, 
at the margin strongly toothed, the ten anterior narrower, slightly 
elevated, toothed at the margin.— Var. Pale yellow.—Var. Tinged 
with red anteriorly.— Ceylon, 
C. Istanpicum. Lin. 1124.—D. p. 128.—Ch. f. 195, 6.—E. t. 
300. f.8.—W. t. 5. f. 27.—Gould. Mas. f. 58.—(Young—C. 
Pusescens. Couthouy.) Large, thinnish, anteriorly longer, rather 
obliquely rounded ovate, tumid, with thirty-six or more three- 
sided sharp-edged radiating ribs, the intervening furrows rounded 
and regularly wrinkled by the lines of growth : beaks prominent, 
almost touching : epidermis yellowish brown, lax, and bristling into 
a stiff fringe on the sharp edge of the ribs: within straw coloured. 
13..2.—N. America, Iceland, Se. 
C. Puncrutatum. Brod. §& Sow. Z. J. 4.—Reeve. t. 84. 
f.7.—C. I. f.7. Suborbicular, with twenty-two elevated rounded 
ribs, the posterior ones, as well as the interstices covered with 
minute raised dots, the anterior with a slender horny fringe of 
epidermis on the front edges: marginal teeth large and deeply cut. 
1,,-. 14. 
'G. Noposum.* Mont. p. 81.—Lin. Tr. 8. p. 66.—Wood. G. 
C. p. 212.—Turt. Biv. p. 186. t. 13. f. 8. Orbicular sub- 
equilateral and rather flat, brown or whitish, very slightly angular 
anteriorly ; with about twenty-six close set rounded ribs thickly 
clothed with obtuse round tubercles which project anteriorly into 
very short spines; inside white with generally a chesnut anterior 
stripe extending half way down the shell. -?;. . <5.—Fingland. 
C. Rigipum. Wood. G. C. t.57.f. 2, 3.—D. p. 126.—W. t. 
5. f.41. Obliquely subcordate, obovate, anteriorly obtusely an- 
gulated and longer, whitish under a strongly adherent wrinkled 
epidermis, with not more than twenty-six prominent radiating ribs 
armed with small deciduous tubercles : inside white, the teeth 
strong. 3..4.—In the Banksian collection. 
C. Ovate.* Sow.—C. Exroneatum. Mont. p. 82.—D. p. 
131.—Turt. B. t. 13. f. 9. p. 185. Oval and oblique, produced 
and a little angular anteriorly, tumid in the middle and sloping to 
the sides ; pale rufous with some .obscure darker anterior spots, 
twenty-five prickly ribs, the central flattened and separated by a 
fine line: beaks prominent. }..+%- 
C. Sicutum. Sow. Jun. Z P. 1841.—C. LI. f. 31. Thin, 
sub-quadrangular, ventricose, posteriorly narrow, anteriorly broad, 
