118 CARDIUM. 



doubting whether it should be considered a distinct species ; 

 the colour is pale whitish brown, with darker transverse 

 bands. 



isocardia. 17. Shell heart-shaped, with longitu- 

 dinal ribs, and erect vaulted scales. 



Cardium Tsocardia. Linnaeus Syst. Nat. p. 1122. Born. 



Mus. p. 4.5 and Vign. at p. 39- Chemnitz, vi. p. 182. t. 



17. f- 174 to 176. Schroeter Einl. iii. p. 38. Gmelin, 



p. 324Q. Bruguiere Enc. Meth. p. 215. Wood's Conch. 



p. 217. t. 52. f. 1 and 2. 

 Cardium squamosum. Gmelin, p. 3256. 

 Bonanni Rec. 2. f» 95 and Kirch, f. 93. Lister Conch. 



t. 323. f. 160. Petiver Gaz. t. 152. f. 7. Gaulter, X. 



71. f. N. Argenville, t. 23. f. M. Seba, iii. t. 86. f. 



5. Regenfuss. i. t. 5. f. 56. Enc. Meth. t. 297. f. 4. 

 Inhabits the Red Sea and Persian Gulf. Bonanni. Coasts 

 of Jamaica. Lister. Nussatello and Hitoe in the Eastern 

 Ocean. Regenfuss. West Indies. Humphreys. 

 Shell about two inches long, and the breadth and height, which 

 are equal, rather exceed an inch and a half; it has about 

 thirty-five longitudinal ribs, covered with erect vaulted scales, 

 and the hinge has only a single primary tooth in each valve ; 

 the outer surface is whitish, with irregular reddish brown 

 spots, and the inside white, stained with purple in . the 

 middle. 



fragum. 18. Shell somewhat heart-shaped, and 

 angulated; ribs armed towards the margin, 

 with numerous elevated crescent-shaped striae. 



Cardium Fragum. Linnaeus Syst. Nat. p. 1123. Chemnitz, 



vi. p. 172. t. 16. f. 166 and 1 67- Schroeter Einl. iii. 



p. 39. Gmelin, p. 3749. Bruguiere Enc. Meth. p. 



212. Wood's Conch, p. 241. t. 58. f. 1 and 2. 

 Cardium imbricatum. Born. Mus. p. 42. t. 3. f. 3 and 4. 

 Bonanni Rec. 3. f. 374. Lister Conch, t. 315. f. 152. 



Rumphius, t. 44. f. G. Petiver Amb. t. 18. f. 21. 



Gualter, X. 83. f. E. Enc. Method. X. 295. f. 3. 

 Inhabits the Asiatic and American Oceans. Linnaeus. Coasts 



of China. Humphreys. 

 The length is usually rather more than an inch and a quarter, 

 the breadth an inch, and the height near eleven lines ; it has 

 on each valve, about twenty-three convex longitudinal ribs, 

 armed with small crescent-shaped scales, which are more 

 crowded at the anterior than the posterior end, and are 



