UNI O. 



4.1 



OVAL. 



Unio orientalis. Bourg. 



*regularis. Lea. Chenu. 

 *Paraguayensis. Lea. 

 Swinhoei. H Adams. Reeve. 

 *amcenus. Lea. Chenu. 

 *Sapotalensis. Lea. Chenu. 

 *Oregonensis. Lea. 

 *Medellimis. 1 Lea. Chenu. Han. 

 *notatus. Lea. Chenu. Han. 

 *micans. Lea. 

 *perlucens. Lea. 

 *subangulatus. Lea. 

 *sparus. Lea. 

 *Veracruzensis. Lea. 

 *scitulus. Lea. 

 *Goascoranensis. Lea. 

 *gracilior. Lea. 

 *obfuscus. Lea. 

 *rutilans. Lea. 

 *subellipsis. Lea. 

 *datus. Lea. 



OVAL. 



Aucklandicus. Gray. 

 *dispar. Lea. 

 *concestator. Lea. 

 *lienosus. 2 Con. Kiist. Han. 

 *calliginosus. Lea. 

 *firmus. Lea. 



*Nashvillensis. s Lea. Han. 

 *contiguus. Lea. 

 *umbrans. Lea. 

 *intercedens. Lea. 

 *fallax. Lea. 

 *obscurus. Lea. 

 *genuinus. Lea. 



*Zieglerianus. Lea. Chenu. Han. 

 *proximus. Lea. 

 *nitens. Lea. 

 *Copei. Lea. 

 *Pybasii. Lea. 

 *proprius. Lea. 

 *tenebricus. Lea. 

 *Prattii. Lea. 



1 Mr. Say's purpuriatus and this maybe the same. I have never seen his specimens, and there is no 

 figure. The description is in the Disseminator, Jan. 1, 1831. 



2 Mr. Conrad, in his Monograph of Unionidx, p. 61, considers Nashvillensis, Lea, to be the same 

 with lienosus, Con.; but the former shell is certainly not the species figured by him pi. 34, f. 2. 



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