3(J COKIKIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY 1. 



therefore an Erimyzon and not a '■'■ Ptychostoiims''''. Both E. oblongiis 

 and E. mclanops abound in the lakes as well as in the Ohio. They are 

 much more tenacious of life than the other Suckers. The description of 

 Cyprimis sucetta Lacepede (Catostomus suceti 0. & V.) seems to refer to 

 this species. I therefore have adopted the prior name sucetta in prefer- 

 ence to that of melanops. 



The "lateral line" alluded to by Eafinesque here, as in numerous 

 other instances, is merely a lateral streak along the rows of scales, either 

 due to longitudinal furrows or else to peculiarities of coloration. 



*61st spscies, Black-back Sucker, CATOSTOr/EUS MELANOTUS, Ca- 

 tostome melanote. (p. 58 J 



? CAjMPOSTOma anomalum (Kaf.) Ag. 



The " nine dorsal rays" indicates a Cyprinoid, and the only species 

 found at the Falls of the Ohio which at all answers this description are 

 the ^^ocomis biguttatiis and Campostoma anomalum. It is best to iden- 

 tify it with the latter, and thus to avoid a change of names. 



t62d species, Rough-head Sucker, CATOSTOMUS FA2CIOLARIS, Ca- 

 tostome fascia, (p. 58.) 



Erimtzon 0I3L0^;gus (Mitch.) Jor. 



Moxostoma ohlongum (Mitch.) Ag. 



Description indiiferent, "from a drawing by Mr. Audubon". The 

 tuberculated snout indicates a spring male of oblongus, rather than ni- 

 gricans, to which Professor Agassiz refers Rafinesque's description. 



* Diameter one-eistli ofthe length; blnish black above, whitish beneath; head con- 

 vex, SDout obtuse ; lateral line straight; dorsal and anal fins with nine rays. 



Seen only once at the falls. Length 6 inches, body nearly cylindrical. Mouth 

 rather inferior, lips thick and somewhat gristly. Iris silvery. Scales pretty large. 

 Fius whitish, the dorsal and caudal a little reddish. Pectoral fins elliptical with 16 

 rays. Tail 20. Dorsal fin trapezoidal, opposed to the abdominal, the first ray shorter. 

 Anal elliptical obtuse. Vulgar names, Black Sucker and Blue Sucker, 



t Diameter one-sixth of the length; brown above, white beneath, sides with small 

 transversal black lines; head sloping, tuberculated above, snout obtuse; dorsal fin 

 longitudinal reaching the end ofthe anal tin, lateral line straight. 



I have not seen this species, but describe it from a drawing of Mr. Audubon. It id 

 found iu the lower part ofthe Ohio. Vulgar names : Rough-head Sucker, Pike-Sucker, 

 Striped Sucker. Length about eight inches, body cylindrical tapering behind. Eyes 

 small, month beneath. Lower fius trapezoidal, about twenty transversal lines. A 

 doubtful species, perhaps an Hydrargyrus, but the mouth is like that of the Sucker. 



