114 CARDIUM. 



St. Croix, and St. Thomas. Chemnitz. Britain. Donovan. 

 Shell about an inch and a half long, almost equally broad, and 

 near an inch high ; whitish, marbled or spotted with reddish 

 brown, and marked with strong convex longitudinal ribs, se- 

 parated by almost equally broad furrows, and crossed by 

 minute transverse striae ; the anterior side is somewhat trun- 

 cated, flattish, and slightly keeled at its border, but becomes 

 elevated towards the margin of the valves. 



donaciforme. 10. Shell somewhat heart-shaped, 

 longitudinally grooved, and the anterior end 

 truncated; umbones cancellated. 



Cardium donaciforme. Schroeter Einl. iii. p. 68. t. 7- 

 f. 14. Bruguiere Enc. Meth. p. 214. Schreber's Conch* 

 i. p. 71. IVood's Conch, p. 234. 

 Cardium medium Var. Chemnitz, vi. p. 17 1- t« 16. f. 165 

 Gmelin, p. 3247- 

 Inhabits the coasts of the West India Islands. Chemnitz. 

 This species differs from C. medium in being broader than it is 

 long, more strikingly truncated at the anterior end, and the 

 longitudinal ribs separated only by narrow shallow grooves ; 

 it is also said to have the primary teeth closer, and the lateral 

 teeth much pointed in one, and very obtuse in the other 

 valve. 



exiguum. 11. Shell somewhat heart-shaped, and 

 obliquely angulated at the anterior end ; ribs 

 imbricated, and the interstices grooved trans- 

 versely. 



Cardium exiguum. Gmelin, p. 3255. Montagu Test. p. 82. 



Maton and Racket, in Lin. Trans, viii. p. 61. Dorset 



Cat. p. 3 I. t. 2. f. 1 1 . Wood's Conch, p. €12. 

 Cardium pygmaeum. Solanders MSS. Donovan, i. t. S2. 



f. 3. 

 Lister Conch, t. 317- f. 154. Petiver Gaz. t. 93. f. 11. 



Walker's Min. Shells, f. 83. 

 Inhabits the coasts of England. Lister, fyc. 

 Shell about four lines and a half long, five broad, and three 

 and a half high ; pale tawny white, with about twenty 

 angulated ribs, and their interstices strikingly grooved trans- 

 versely. 



aculeatum. 12. Shell somewhat heart-shaped, with 



