GEOGRAPHICAL DISTRIBUTION OF NEW YORK UNIONISE 59 



New Jersey. 



Raritan river, Somerville Walker. 



Pennsylvania. 



Philadelphia Coll. Phila. Acad. 



Delaware. 



Marsh. 



District of Columbia. 

 Potomac river Sterki, Hinkley. 



Virginia. 



Canal at Alexandria Sterki. 



Occurs in the eastern and St. Lawrence drainage systems. 

 One of the most characteristic of our eastern species. 



Unio clavus, Lam. 



Ontario. 



Toronto — occurs fossil Simpson. 



Pennsylvania. 



Allegheny river, Warren county Beecher. 



Ohio. 



Scioto river Walker. 



Mahoning river Walker. 



Ohio river system Sterki. 



Indiana. 



Wabash river Hinkley. 



Shelby county Hinkley. 



White river Walker. 



Illinois. 



Marsh. 



Tennessee. 



Marsh. 



Alabama. 



Marsh. 



In all probability U. patulus is a synonym of this species. In 

 the living state U. clavus is found only in the Mississippi drain- 

 age system. Mr. Chas. T. Simpson has recorded it as occurring 

 fossil at Toronto, Ontario — in the St. Lawrence drainage system. 



