60 GENUS VII. CARDIUM. 



Mr. Monta^ has placed Tellina, Cornea, amnicum, laciis- 



tris, and pisiformis in this genus. 



Lamarck has made no alteration in this genus, but describes 



it as follows : 



Cardium. Shell somewhat heart-shaped, the valves toothed 

 or folded at the edge ; hinge with four teeth, of which 

 the two centre ones are approaching oblique in each 

 valve, articulating crossways with the opposite ones ; the 

 lateral ones remote and intmded (Cardium Unedo Linn. 

 See pi. 2. f. 19). 



