300 ORTMANN— THE ALLEGHENIAN DIVIDE. [April i8. 



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. Plenrohema obliqnum coccincum (Conr.) 



2. Plenrohema clava (Lam.) 



3. EUiptio dilatatus (Raf.) 



4. Syiiiphynofa costata (Raf.) 



5. Alasuiidonta inarginata (Say) 



6. Strophitus edentulns (Say) 



7. Ptychohranchiis phaseolus (Hildr.) 



8. Lampsilis ovata ventricosa (Barn.) 



9. Lampsilis midtiradiata (Lea) 



Also Anodonta grandis Say should be mentioned, but this has 

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

 ligamentiiia (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 Queiiiahoiiiiig Creek, in Somerset Co., I collected: 



List No. p. 



1. Elliptio dilatatus (Raf.) 



2. Symphyjiota costata (Raf.) 



3. Alasmidonta marginata (Say) 



4. Strophitus edenttdiis (Say) 



5. Ptychobranchus phaseolus (Hildr.) 



6. Lampsilis ovata ventricosa (Barn.) 



7. Lampsilis midtiradiata (Lea) 



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

 (nos. I and 2) are lacking. 



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



