310 MARINE SHELLS 



Length half an inch. 



Breadth thirteen-twentieths of an inch. 



Thickness seven-twentieths of an inch. 



Inhabits the coast of the United States. 



Cabinet of the Academy and Philadelphia Mu- 

 seum. 



A very common shell on almost all parts of our 

 coast. 



V 



3. M. *oblonga. Shell transverse, oblong-oval ; 

 very slightly wrinkled, excepting upon the margin ; 

 umbo hardly prominent ; two strong distant lines or 

 folds drawn from the apex to the anterior extremity 

 of the shell ; colour dull whitish, hardly polished, 

 umbo slightly tinged with ferruginous, within white, 

 highly polished. 



Length nine-twentieths of an inch. 



Breadth one inch and nine-tenths. 



Inhabits the coast of Georgia. 



Cabinet of the Academy and Philadelphia Mu- 

 seum. 



Of this species I found but three valves, on one of 

 the sea islands of Georgia. 



LUTKAHIA, Lam. 



Species, 



1. L. Hineata. Shell transversely suboval, thin, 

 white, tinged with ferruginous ; posterior hiatus pa- 

 tulous, anterior one linear and commencing below 



