BEAKS OF UNIONID.F 



173 



A list of the species inhabiting the vicinity of Albany is 

 given below, arranged in the same order of sequence as in 

 Lea's Synopsis of the Unionidse : 



Genus MARGARON 

 Subgenus Unio 



Symphynote, smooth, oblong 

 Non-symphynote, smooth, oval 



U. pressus, Lea.* Syn. p. 29 



' oblong — 

 ' wide — 

 ' obovate — 



OCHRACEUS, Say " 



C ARIOSUS, Say " 



luteolus, Lam " 



radiatus, Lam " 



COMPLANATUS, Sol " 



NASUTUS, Say " 



Tappanianus, Lea " 



Subgenus Margaritana 



Non-symphynote, plicate, oblong — M. marginata, Say " 



" " " " — " rugosa, Barnes " 



" " smooth, triangular — " undulata, Say " 



42 

 42 

 44 

 44 

 5i 

 60 

 62 



67 

 67 

 68 



Subgenus Anodonta 



Non-symphynote, smooth, oval — A. undulata, Say " " 79 



" ' " '• " — " implicata, Say " ; ' 80 



" " " " — " FLUVIATILIS, Dillw " " 80 



" " " — " Lewisii, Lea " " 80 



" " " wide — " SUBCYLINDRACEA, Lea " " 82 



For the synonyms of the above species the reader is referred to Lea's Synopsis at 

 the pages indicated to the right in the above list. 



In the text of this paper the species are considered in the 

 order of sequence indicated by the relationship of beak 

 characters. Arranged upon this basis the species of the 

 foregoing list fall into the following order : 



Unio pressus, Lea 

 Unio Tappanianus, Lea 



Unio luteolus, Lam. 

 Unio radiatus, Lam. 



Unio nasutus, Say 



Unio complanatus, Sol. 



Unio ochraceus, Say 

 Unio cariosus, Say 



Margaritana marginata, Say 

 Margaritana rugosa, Barnes 



Margaritana undulata, Say 



