CARDIUM. 113 



Shell varying from one to two inches in length, and the breadth 

 and heightli are each about equal to three-fourths of die 

 length ; the colour is white, and shining, or sometimes pale 

 yellow, and occasionally spotted with red ; there are in each 

 valve about twenty-one longitudinal crenulated grooves, whose 

 intermediate ribs are more or less tuberculated, and the deep 

 crescent-shaped cavity, which is placed immediately below 

 the umbones, is of itself sufficient to distinguish this species, 



hemicardium. 8. Shell heart-shaped, sub-trilate- 

 ral, keeled at the anterior end, and marked 

 with punctured grooves ; umbones distant. 



Cardium hemicardium. Linnaeus Syst.Nat. p. 1121. Born. 



Mm. p. 42. Chemnitz, vi. p. 167. t. \6. f. 159 to l6l. 



Schroeter Einl. iii. p. 3 1 . Gmelin, p. 3246. Bruguiere 



Enc. Meth. p. 211. Wood's Conch, p. 240. t. 57- f. 7 



and 8. 

 Rumphius, t. 44. f. H. Petiver Amb. t. 17- f- 4. Gualter, 



t. 83. f. C. Knorr, vi. t. 3. f. 2. Enc. Meth. t. 295. 



f.2. 

 Inhabits the coasts of Amboyna. Rumphius. Molucca Islands, 



Chemnitz. China. Humphreys. 

 The length is usually an inch and a quarter, and the breadth and 

 height an inch ; there are on each valve about twenty-four 

 ribs, which are tuberculated at the posterior end, and the in- 

 termediate grooves are marked with excavated dots ; the co- 

 lour is whitish, or pale yellow, and the inside white. 



medium. 9. Shell somewhat heart-shaped, angu- 

 lated at the anterior end, and marked with 

 rounded longitudinal ribs, and minute trans- 

 verse stria?. 



Cardium medium. Linn&us Sust. Nat. p. 1122. Born. 

 Mus. p. 43. Chemnitz, vi. p. 169. t. 16. f. 162 to 1 64. 

 Schroeter Einl. iii. p. 32. Gmelin, p. 3246. Bruguiere 

 Ene. Meth. p.- 2 13. Donovan, i. t. 32. f. 1. Montagu 

 Test. p. 83. Mat on and Racket, in Lin. Trans, viii. 

 p. 61. Wood's Conch, p. 211. t. 50. f. 3. 

 Bonanni Rec. 2. f. 94. and Kirch, f. 91. Lister Conch, t. 

 316. f. 153. Gualter, t. 83. f. B. Knorr, ii. t. 29- 

 f. 5. and v. t. 20. f. 5. Favanne, t. 51. f. I. 3. Enc. 

 Method, t. 296. f. 1. 



Inhabits the coasts of Jamaica. Lister. Islands of Antigua, 



VOL. I. i 



