120 CARJDIUM. 



is almost equal ; the shell is strong, white, with only a tinge 

 of rose colour on both sides of the margin ; it has about 

 twenty-six longitudinal ribs, forming corresponding serratures 

 on the margin, of which seven are very deeply cut, and do 

 not lock into those of the opposite valve, when the valves are 

 shut. 



muricatum. 21. Shell ovate-heart-shaped; ribs 

 armed with oblique flattish spines, pointed in 

 different directions. 



Cardium muricatum. Linnaus Syst. Nat. p. 1 123. Chem- 

 nitz, vi. p. 185. t. 17. f. 177 and 178. Schroeter Einl. 

 iii. p. 41. Gmelin, p. 3250. Bruguiere Enc. Metk. 

 p. 253. Wood's Conch, p. 21 6. t. 51. f. 2 and 3. 

 Lister Conch, t. 322. f. 159. Knorr, iv. t. 14. f. 5. 

 Inhabits the coasts of Jamaica. Lister. St. Domingo. Bru- 

 guiere. West Indies. Humphreys. 

 Shell about eighteen lines long, sixteen broad, and thirteen 

 high ; of a greyish or yellowish white colour, edged with 

 orange, yellow, or scarlet, on the anterior side, and some- 

 times stained or spotted with red. There are thirty-six lon- 

 gitudinal ribs, of which twelve have their spines pointed in 

 an opposite direction to the others ; the marginal serratures 

 are largest on the anterior edge. 



magnum. 22. Shell oblong, with angulated grooves, 

 serrated on the side. 



Cardium magnum. Linnceus Syst. Nat. p. 1123. 



Inhabits Jamaica. Linnceus. 



Linnaeus, in the Systema Naturae, has referred only to the Mus. 

 Lud. Ulrica, and he there describes this shell to be " ob- 

 long, ovate, as big as a hand, with nineteen angulated 

 grooves crenated backwards; margins reddish within, toothed 

 at the apex, and seriated on the sides ; colour pale on the 

 out, and reddish in the inside ; in the area on the posterior 

 side, the cleft by the cartilage, and the teeth of the hinge, it 

 resembles C. muricatum." Bruguiere has given many reasons 

 (Enc. Meth. p. 229.) for supposing that C. leucostomum is 

 this species, and that the number of ribs in the above des- 

 cription has been misprinted 19 instead of 39, and he consi- 

 ders the figure referred to by Chemnitz and Gmelin, (Chem- 

 nitz, t. 19. f. 191.) for C. magnum to be the same shell or a 

 variety in a more advanced stage of growth ; in all other re- 

 spects C. leucostomum agrees much better with the Linnaean 



