60. 



u X I o . 



fWIDE. 



Unio Gargottse. P/dli. Jlore. Gerst. 

 Hossm. 



*Moreleti.' Desk. 



*sagitt£eformis. Lea. 



*rostriforniis. Lea. 



*gracilentus. Lea. 



*nasutus.^ Say. Barn. Swain. Llan. 

 Gould. Linsl. Delcay. 

 Unio rostratus. Valen. 

 Ifya nasuta. Wood. Eat. 

 Eurynea nasuta. Stimjison. (Agass. 

 MSS.) 



*Mississippiensis. Con. 

 Unio Cocoduensis. Reeve. 



*aquilus. Lea. 



*protensus. Lea. 



*extensus. Lea. 



*Burkeiisis. Lea. 



*ob]atus. Lea. 



*Macoiiensis. Lea. 



'WIDE. 



*naviculoides. Lea. 



*perlatus. Lea. 



*Hazleliurstianus. Lea. 



*Barrattii. Lea. 



productiis.^ Con. Kilst. Llan. 



*viridiradiatus. Lea. 



*pullatus. Lea. 



*Fisberianus. Lea. Chenu. LLan. 



*iiasutuliis. Lea. 



*Emmonsii. Lea. 



*alieneus. Lea. \ 



*Jayanus. Lea. Chenu. Llan. 



*marginalis. Lam. Desk. Blan. Llan. 

 Unio anodontina. Lam. Blan. 

 Unio evanescens? Mouss. 



*iris/ Lea. Desli. Chenu. Han. 

 Unio sulrostratus. Say. 

 Unio nelulosus? Con. 



*]Srovi-Eboraci.^ Lea. Delcay. Chenu. 



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

 Rev. Mr. Beadle, of Hartford, Conn. 



'^ Mr. Agassiz says that the genus Unio., Retz., is represented in this country by U. nasutus, Lam. 

 Lamarck's ndsutus is gibbosus, Bar. Mr. Saj^ preoccupied the name riasutus 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 synonj-m to gibbosus, Bar. 



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



* Mr. Say, in his Synonymy, gives iris as a synonj'm 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 descriiDtion, however, of subrostratus does not ajDply to mj^ iris, and certainly this shell could not 

 have been under his eye when his descrijjtion was made. He says that the subi-ostratus "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 sj^ecies may have been described by him for subrostratus. 



^ Novi-Ehoraci 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., N. S., and Observations 

 on Unio, vol. s. 



