38 



U N 10. 



fWIDE. 



*lugubris. Lea. Chenu. 



*marginalis. Lam. 



Unio anodontina. Lam. 



*iris.' Lea. Desk. Chenu. 

 Unio nebulosus. Con. 



*fatuus. Lea. Chenu. 



*tenuissimus. Lea. 



Symp. tenuissima. Lea, in Trans. 



Am. P. S. 

 An. purpurascens. Swain. 

 Unio velum. Say. 

 Unio leptodon. Con. 

 Unio planus. Con. 



*bilineatus. Lea. Ben. 



Symp. lilineata. Lea, in Trans. Am. 

 P. S. 



*Corrianus. Lea. 



*orientalis. Lea. Chenu. 



*phaseolus. Sild. Bat. 



Unio planulatus. Lea. Desk. 



Chenu. 



Unio cuneatus. 2 Barn. (White var.) 



arcus. Con. 



arctatus. Con. 



( WIDE. 



*gibbosus. Bar. Eat. Sild. 

 Unio mucronatus. Bar. 

 Unio nasuta. Lam. Cuv. 

 Unio dilatata? Raf. 

 Unio dilatatus. Con. Kiist. 



*arctior. Lea. Chenu. 



*Patagonicus. JD' Orb. 



*Vaughanianus. Lea. Chenu. 



Unio Carolinensis. Prof. Ravenel'i 

 Letter. 



OBOVATE. 









*purpuratus. 



Lam. Potier 





Mya ventricosa. 3 



Solan. 



Hum- 



phreys ? 









Unio ater. 



Lea 



. Besh. 



Chenu 



Unio lugub 



ris. 



Say. 





Unio Poulsoni. 



Con. 





*biangulatus. Lea. Chenu. 



rhombeus. Wag. 

 Biplodon rhombeum. Spix. 



*cuprinus. Lea. Chenu. 

 Unio metallicus. 4 Say. 



*papyraceus. Gould. 



*Boydianus. Lea. Bekay. Chenu. 



1 Mr. Say, in his Synonymy, gives iris as a synonym to his subrostratus. If they were the same, I would be 

 entitled to precedence, as my description bears date March, 1829, while his is January, 1831. His description, 

 however, of subrostratus does not apply to my iris, and certainly this shell could not have been under his eye when 

 his description was made. He says that the subrostratus " may be said to be the analogue of the Unio nasutus 

 (nobis) of the western waters." As the U. nasutus inhabits the western waters, a variety of that species may have 

 been described by him for subrostratus. 



2 In note to Dr. Hildreth's Memoir on the shells in the vicinity of Marietta, Ohio, published in Suliman's 

 Journal. 



3 Fide Ferussac. 



4 Mr. Say, in his Synonymy, claims precedence. My Memoir bears the date of May 7, 1830 j his that of 

 January 1, 1831. 



