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WIDE. 



Unio Gargottse. Phili. More. Gerst. 

 Rossm. 



*Moreleti. 1 Desk. 

 *sagittseformis. Lea. 

 *rostriformis. Lea. 

 *gracilentus. Lea. 



*nasutus. 2 Say. Barn. Swain. Han. 



Gould. Linsl. Dekay. 

 Unio rostratus. Valen. 

 Hya nasuta. Wood. Eat. 

 Eurynea nasuta. Stimpson. (Agass. 

 MSS.) 



*Mississippiensis. Con. 

 Unio Cocoduensis. Reeve. 



*aquilus. Lea. 

 *protensus. Lea. 

 *extensus. Lea. 

 *Burkensis. Lea. 

 *oblatus. Lea. 

 *Maconensis. Lea. 



WIDE. 



*naviculoides. Lea. 



*perlatus. Lea. 



*Hazlekurstianus. Lea. 



*Barrattii. Lea. 



productus. 3 Con. Kust. Han. 



*viridiradiatus. Lea. 



*pullatus. Lea. 



*Fisherianus. Lta. Chenu. Han. 



*nasutulus. Lea. 



*Emmonsii. Lea. 



*aheneus. Lea. 



*Jayanus. Lea. Chenu. Han. 



*marginalis. Lam. Desli. Blan. Han. 

 Unio anodontina. Lam. Blan. 

 Unio evanescens? Mouss. 



*iris. 4 Lea. Desli. Chenu. Han. 

 Unio sultrostratus. Say. 

 Unio nelulosus? Con. 



*Novi-Eboraci. 5 Lea. Dekay. Chenu. 



1 This is no doubt a good species. I have seen a very good specimen belonging to the cabinet of the 

 Rev. Mr. Beadle, of Hartford, Conn. 



2 Mr. Agassiz says that the genus C/nio, Retz., is represented in this country by U. nasutus, Lam. 

 Lamarck's nasutus is gibbosus. Bar. Mr. Say preoccupied the name nasutus in 1816. Lamarck published 

 in 1819. In the synonymy of gibbosus, I have in all my editions of this work placed Lamarck's nasutus 

 as a sjTionym to gibbosus, Bar. 



' This is probably the same as folliculatus, Lea, which latter name has precedence. 



* Mr. Say, in his Synonymy, gives iris as a synonym to his sub rostratus. If they were the same, I 

 would be entitled to precedence, as my description bears date March, 1829, while his is January, 18.31. 

 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 tubrottnxttu "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 variet}- of that species may have been described by him for subrostratus. 



6 Novi-Eboraci and iris are in the outlines nearly identical, but in the soft parts there are differences 

 which I have pointed out in the Journal of the Academy Nat. Sciences, vol. v., X. S., and Observations 

 on Unio, vol. x. 



