THE FAMILY NAIADES. 



23 



in 

 H 



O 



I— I 



o 

 ;^ 



I 



O 



o ' 



CO 



OVAL. 



Lecontianus. Zea. 



perdix. Z<ea. 



pectorosus. Co7i. 



ventricosus. Bar. 



occidens.* Lea. 



Unio ventricosus. Say. 



globosa. Lea. 



Sym. globosa. Lea, Trans. Am. Phil. Soc. 

 Unio capax? Green. 



ochraceus. Say. Con. 



Sym. ochracea. Lea, Trans. Am. P. S. 



splendidus. Lea. 



cariosus. Say. Bar. 

 Unio cariosa.t Lam. 

 Unio ovata. Valen. 

 Unio luteola. Con. ; not of Lam. 



perovatus. Con. 



* This and the preceding shell are so nearly allied, that it is a matter of 

 doubt with me if it would not be preferable to unite ihem. Subsequent ex- 

 amination may throw sufficient light upon them to decide with certainty. 

 Among Mr. Barnes's varieties of ventricosus, it is evident there are several 

 distinct species. 



•j- U. cariosa, Lam. (Var. 2,) is the Alas, marginata, Say. 



