UNIO COMPLANATUS. 



Vai\ Suhinjiatus. 

 Plate IX.— Fz^. 2. 



DESCRIPTION. 



Shell elliptical, elongated, slightly ventricose over 

 the umbo and umbonial slope, which is rounded; 

 beaks obsolete; posterior extremity subangular; co- 

 lour olive brown, with green rays; cardinal teeth ro- 

 bust, sulcated; within purplish, and highly iridescent 

 posteriorly. 



OBSERVATIONS. 



Inhabits Savannah and Congaree rivers, S. Caro- 

 lina. Distinguished from variety cariniferus, by the 

 ventricose beaks and umbonial slope, and by the pos- 

 terior dorsal margin, which is rounded at the extremi- 

 ty in this variety, but angular in the cariniferus. 



MELANIA FORMOSA. 



Plate l^i.—Fig. 3. 



DESCRIPTION. 



Shell with distant robust rounded ribs, and six 

 convex whirls, with two approximate prominent 



