THE FAMILY NAIADES. 



25 





WIDE. 



*iris.f Lea. 



Uaio nebulosus. Con. 



*tenuissimLis. Lea. 



Symp. tenuissima. Lea, iu Traus. 



Am. P. S. 

 An. purpuiascens. Swain. 

 Uiiio velum. Say. 



*bilinea(us. Lea. Ben. 



Symp. bilineata. Lea, in Trans. Am. 

 P. S. 



*Coriianus. Lea. 



*pliaseolus. Hild. Eat. 

 Unio planulatus. Lea. 



Unio ciineatiis.| Barn. 

 var.) 



areas. Con. 



arctatus. Con. 



*gibbosus. Bar. Eat. Hild. 

 Unio mucronatus. Bar. 

 Unio nasuta. Lam. 

 Uniodilatata? Raf. 

 Unio dilatatus. Con. 



*arctior. Lea. 



*Patagonicus. D'Orb. 



(White 



w 

 z 

 o 



s 



z^ 



WIDE. 



*Vauglianianus. Lea. 



Unio Carolineiisis. Pro/. RavcneVs 

 Letter. 



OBOVATE. 



*puipuratus. Lam. 



Mya ventricosa.§ Solan. Hum- 

 phreys ? 

 Unio ater. Lea. 

 Unio lugubris. Say. 

 Unio Poulsoni. Con. 



rhombeus. Wag. 



Dipiodon rliombeum. Spix. 



*cuprinus. Lea. 



Unio metallicus.|| Say. 



*modioliformis. Lea. 

 Unio delumbis. Con. 



*teneriis. Rav. 



Unio tenebrosus. Con. 



"Tappanianus. Lea. 



*contradens. Lea. 



stramineiis. Con. 



t 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 ray description bears date March 1829, while his is January 1831. His descrip- 

 tion, 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. 



X In note to Dr Hildreth's Memoir on the shells in the vicinity of Marietta, Ohio, published in Silliman's 

 Journal. 



§ On the authority of Ferussac. 



II Mr Say in his " Synonymy" claims precedence. My Memoir bears the date of May 7, 1830 ; his that of 

 January 1, 1831. 



