TRIBE CARDIACEA. 151k 
—Ch. f. 49, 50.—E. t. 296. f. 6.—C. Sorentrorme. Brug. no. 
34.—Wood. G. C.t.56. f. 3.—W. t. 5. f. 36. Transversely ovate, 
the anterior end produced gaping and serrated at the margin, the 
posterior short narrow and obliquely rounded ; fragile with ob- 
liquely radiating ribs, which are armed at both slopes, white 
marbled with reddish chocolate and a faint purplish spot at the 
beaks visible within and without. 14—AMartinique. 
C. Psevporma. Lam. 13.—C. I. f. 67.  Heart-shaped, 
ventricose, white with thirty-eight flattened ribs which at the 
umbones are smooth, and towards the margin become roughened 
by a central row of minute tubercles. 42.—Red Sea. 
C. Tuspercutatum.* Lin. 1122.—D. p. 117.—Lam. 16.— 
KH. t. 298. f. 3?—Turt. Dic. f. 12.—Don. 3. t. 107. f. 2.— 
Wood. G. C. t. 50. f. 2.—W. t. 5. f. 4. Somewhat globular and 
ponderous, a little truncated anteriorly, brownish, with twenty- 
one ribs which as well as the interstices are coarsely wrinkled 
transversely, the anterior ones armed with pointed tubercles, the 
posterior with thick transverse scale-like plates. 34.— Young. 
Strong, chocolate with white blotches, tuberculated.— Hngland, &c. 
C. Acutgeatum.* Lin. 1122.—D. p. 114.—Lam, 14.—E. t. 
298. f. 1.— Ch. f. 156.—List. 321. f. 158.—Don. t. 6.-—Twurt. 
Biv. t. 13. f. 6, 7.—W. t. 5. f. 1. Somewhat globular, tumid, 
not ponderous, brownish, a little angular on the anterior side, 
with twenty-one ribs armed with transversely compressed spines, 
which anteriorly are more acute, and posteriorly rather warty ; the 
interstices striated transversely. 31.—Hurope.t 
C. Ecurnatum.* Lin. 1122.—D. p. 116.—LZam. 12. Don. t. 
107. f.1.—Dorset Cat. t. 6. f. 2—W.t. 5. f. 2. Somewhat 
globose, convex, not thick, brownish white, slightly oblique, with 
eighteen ribs armed with numerous sharp white spines which 
curve towards the anterior side, and posteriorly are thicker and 
more obtuse : the interstices transversely striated. Diam. 2.— 
Young as the last, but entirely white.—Hurope. 
C. Errnaceum. Zam. 15.—Sprnosum. D. p. 115.—E. ¢. 
297. f. 5.—Ch.f. 157. Rounded heart-shaped, nearly equilateral, 
whitish or tawny, with about thirty-five crowded longitudinal ribs, 
which are marked along the middle with an obsolete groove, are 
closely set with sharp spines anteriorly, and posteriorly with short 
very obliquely mucronated tubercles. 3..3.— Mediterranean. 
C. Isocarpia. Zin. 1122.—D. p. 118.—Lam. 17.—W. t, 5. 
f. 13.—Ch. f. 174, 5, 6.—E. t. 297. f. 4.— Wood. G. C, t. 52. 

1 The young of this species form the C. Ciriare. Lam. 11.— 
(W. t. 5. f. 3.) and are fragile, glossy fawn colour, with the spines 
longitudinally dilated at the base. 
K 2 
