SYNOPSIS OF THE CYPKINIDJE OF PENNSYLVANIA. 



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Ohio. 

 Hypsilepis Kentukiensis. 

 Hypsilepis dipkemia. 

 Clinostomus prorigcr. 

 Clinostomus elongatum. 



Photogenis loucops. 



Albumellus rubrifrons. 

 Chrosomus erythrogaster. 

 Hyborhynohus notatus. 

 Cainpostoma dubium. 

 Erioymba bueoata. 



Susquehanna. 

 Hypsilepis Kentukiensis. 



Clinostomus funduloides. 

 Clinostomus margarita. 



llybopsis proonc. 



Ilybopsis hudsonins. 

 Clirosomus eos. 



Kxoglossum maxillingua. 



Delaware. 



Hypsilepis Kentukiensis. 



Clinostomus funduloides 



Ilybopsis chalybaeus. 

 llybopsis proenc. 

 Hybopsis bifrenatus. 

 Ilybopsis budsonius. 



The species inhabiting waters flowing into Lake Erie, are not determined. Among 

 many occurring in the Ohio list above, may be selected with certainty Stilbe americana, 

 Hypsilepis cornutus, and Hyborhynclms notatus ; add Hybopsis storcrianus and H. hud- 

 sonius. 



It appears then that five species are common to all three river basins ; that one species 

 occurs in the Ohio and Susquehanna that is not found in the Delaware, and five species 

 in the Delaware and Susquehanna, not occurring in the Ohio. Species as yet peculiar to 

 the Ohio, ten ; peculiar to the Susquehanna, four ; peculiar to the Delaware, two. These 

 figures will be more or less changed by future investigations. 



In examining the pharyngeal teeth of the smaller Cyprinichr, the student must be care- 

 ful to observe the character of the masticatory surface. A lateral bevel of the edge of the 

 tooth, sometimes somewhat obliquely turned, has much the appearance of such a surface 

 to the unpractised eye ; it however leaves the cutting edge of the tooth clearly marked. 

 On the other hand, the masticatory surface constitutes a complete and usually broad trun- 

 cation throughout the length of the portion, otherwise occupied by the edge. In young 

 individuals of many genera, the edges of the teeth are serrate. This is persistent in the 

 adults of the genus Stilbe, and of some species of Hypsilepis ; in Europe it characterizes 

 Scardinins. 



It may be premised, that in the following descriptions the scales are counted from the 

 origin of the first dorsal ray, to that of the ventral, never including those of the vertebral 

 series. 



The peculiarities of the Cyprinoid fauna of the Eastern district of North America, i. e., 

 from the Atlantic Ocean to the base of the Rocky Mountains, as compared with the Palse- 



