TRIBE CARDIACEA. 149 



short, the anterior elongated ; with a few broad radiating ribs, the 

 posterior ones transversely decussated, the central anteriorly angu- 

 lated, the anterior rounded, dorsal edge scaly, to'-^to' — West 

 Colombia, and Panama. 



C. Affinis. Sow. Z. P. 1832.— Reeve. Ic. t. \.f. 6. Oblong, 

 pale mottled with fuscous, posteriorly short, anteriorly elongated ; 

 a few radiating broad ribs which posteriorly are somewhat indistinct, 

 anteriorly prominent angular and rather scaly, -f^ . . 1J. — Central 

 America. — Is this distinct from Pectunculus? 



C. Pectunculus. Brug.p. 412. — Reeve. Ic. t. \.f 4. — Chama 

 P. D.p. 220.— W. t. 9.f. 16.— Lis. t. 347. f. 185. Transversely 

 elongated, oblong, rounded at both ends, posteriorly very short, 

 anteriorly produced and rather dilated, ventral edge incurved sub- 

 centrally : thick moderately convex, brownish, with from eighteen to 

 twenty smooth convex radiating ribs : inside reddish, i . . 1-^. — 

 South America ? 



C. Incrassata. Sow. Tanh.— W. S. t. 2. /. 3.— C. Rubi- 

 cunda, Menke Cat. Transversely oblong, subrhombic, the liga- 

 mental edge being almost parallel to the scarcely curved ventral, 

 posteriorly very short ; white or orange flesh colour, with sixteen 

 thickened, elevated, rounded, crenated ribs, the interstices narrow : 

 uniform white within. 2 



CYPRICARDIA. 



Free, equivalve, inequilateral, obliquely or transversely elongated; 

 primary teeth three, situated under the beaks, and one lateral 

 tooth produced under the anterior depression. 



C. Guiniaca. Lam. 1. — Chama Oblonga. Lin. 1139. 

 D. p. 219.— Ch. f. 504, 5.—F. t. 234. /. 2.—BI. t. 65. bis. 

 f. 6. — W. t. 9. f. 14. — Oblong, the anterior slope obliquely 

 angulated and compressed towards its extremity, yellowish white, 

 decussated by fine strise, apex rounded : white within. 2J-. — - 

 Guinea. — Has the look of a 3Iodiola. 3 



C. Angulata. Lam. 2. — Ch.f. 1993, 4. — Chama Rostrata. 

 IV. S. t. 2. f. 2. Oblong, obliquely angulated anteriorly, trans- 

 versely grooved and decussated by longitudinal strise, white and 

 slightly gaping at the base of the anterior side which is obliquely 



2 Probably the Venus Aculeata of Gmelin, (Schroet. Fin. 

 t. 8. /. 13.— D. p. 198.— W. t. 8. f. 89.) belongs to this genus, 

 being described as having two cardinal teeth in each valve. 



3 C. Californica of Conrad differs not in description from this 

 species. — Add the C. Oblonga of Sowerby (not of Lin.) C. An- 

 gulata of W. S. t.2.f 1. 



