Ortmann : Unionid.e of Western Pennsylvania. 201 



A few individuals in the Monongahela and Allegheny represent 

 transititons toward the var. kirtlandiana. 

 45^. Quadrula subrotunda kirtlandiana (Lea). 



Given in Harn's list from western Pennsylvania; occurring in the 

 Beaver, according to Rhoads. It is abundant in the Beaver drainage 

 in the Mahoning and Shenango Rivers in Lawrence and Mercer 

 Counties, and is locally the prevailing species. It also is found in 

 French Creek in Venango and Crawford Counties, as far up as Meadville 

 and Conneaut Outlet. 



At the critical jroints, where the range of this form passes into that 

 of the typical subi-otiinda (lower Beaver River, and the Allegheny in 

 Venango County) the molluscan fauna is destroyed. No typical speci- 

 mens of kirtlandiana have been found in the Monongahela drainage. 

 Some specimens from Charleroi have been named by Simpson " kirt- 

 landiana,^'' but they do not represent the typical phase of this form. 

 46. Quadrula (Rotundaria) tuberculata (Rafinesque). 



It does not occur in the lists of Harn, Stupakoff, and Clapp. It is 

 reported by Rhoads from the Ohio and Beaver. 



A rare species, found sparingly in the Ohio in Beaver County and 

 (formerly) in Allegheny County. It occurs in the Monongahela 

 drainage in Dunkard Creek, Greene County, and the Cheat River, 

 Fayette County ; in the Allegheny in Armstrong and Venango Counties ; 

 and in French Creek in Venango County. A single specimen from 

 the Beaver in Lawrence County is contained in the Clapp & Smith 

 Collection in the Carnegie Museum, but in quite recent years it has 

 not been found in the Beaver drainage. 



B. Lake Erie Drainage. 

 No freshwater mussels have been previously reported from the Penn- 

 sylvanian shores of Lake Erie, and none from the tributaries of the 

 lake in this state. The Carnegie Museum possesses good material col- 

 lected in the lake chiefly at and near Erie, in Presque Isle Bay, and 

 upon Presque Isle. These collections were made by Dr. D. A. At- 

 kinson in August, 1900, by O. E. Jennings in May, 1905, and Sep- 

 tember, 1906, and by the present writer in June, 1908. A few dead 

 shells were secured by the present writer on the lake beach at Miles 

 Grove, Erie County, and a few others in the only tributary of the 

 lake which contains mussels, Conneaut Creek at Springboro, Crawford 

 County. 



