300 ORTMANN— THE ALLEGHENIAN DIVIDE. [April i8 f 



Also this fauna is fragmentary, since these streams are partially 

 polluted. But there are two tributaries of the Kiskiminetas system, 

 in the mountains, between Chestnut Ridge, Laurel Hill Ridge, and 

 Allegheny Front, which have furnished what appears as complete 

 faunas. Loyalhanna River, near Ligonier, Westmoreland Co., 

 contains : 



List No. 8. 



1. Pleurobema obliquum coccineum (Conr.) 



2. Pleurobema clava (Lam.) 



3. Elliptio dilatatus (Raf.) 



4. Symphynota costata (Raf.) 



5. Alasmidonta marginata (Say) 



6. Strophitus edentulus (Say) 



7. Ptychobranchus phase olus (Hildr.) 



8. Lampsilis ovata ventricosa (Barn.) 



9. Lampsilis multiradiata (Lea) 



Also Anodonta grandis Say should be mentioned, but this has 

 been found only in ponds cut off from the river. Of Nephronaias 

 ligamentina (Lam.) a single individual has been found many years 

 ago, but recent investigations have failed to bring it to light again. 



Seven of these species have occurred in the other lists of the 

 tributaries of the Allegheny, while two are new (nos. 2 and 9). 



In Quemahoning Creek, in Somerset Co., I collected: 



List No. p. 



1. Elliptio dilatatus (Raf.) 



2. Symphynota costata (Raf.) 



3. Alasmidonta marginata (Say) 



4. Strophitus edentulus (Say) 



5. Ptychobranchus phaseolus (Hildr.) 



6. Lampsilis ovata ventricosa (Barn.) 



7. Lampsilis multiradiata (Lea) 



All these are also found in the Loyalhanna, but two of the latter 

 (nos. 1 and 2) are lacking. 



The streams belonging to the Allegheny, discussed so far, form 



