44 



LUTRARIA. 



mya oblonga. — Gmelin. 



Gualter, t. 90, /. A. 2. 



This genus is perfectly distinct from the G. Mactra, 

 as it wants the lateral teeth, and by its affinity to 

 the G. Anatina presents a natural transition from the 

 G. Mya. Shell inequilateral transversely oblong or 

 rounded, gaping at the lateral extremities; hinge with 

 one tooth, as it were folded or plaited in two, one side 

 of which is plain, with an opposite hollow to receive 

 it; no lateral teeth, ligament interior and fixed in the 

 hollow cavities of the primary teeth. 



Shell transversely oblong. 



Lutraria solenoides Lutraria elliptica 

 Lutraria rugosa. 



Shell orbicular or subtriangular. 



Lutraria compressa Lutraria papyracea 



piperata •/ plicatella 



1 il I monies crassiplica 



Candida complanata. 



