116 ICHTHYOLOGIA OHIENSIS 



inal. Tail with 20 rays. Scales rather large ner- 

 vosa radiated. 



6 1 St Species. Black-back Sucker. Catostomus 

 melajwttis. Catostome melanote. 



Diameter one sixth of the length : bluish black a- 

 bove, whitish beneath ; head convex, snout obtuse : lat- 

 eral line straight : dorsal and anal fins with nine rays. 



Seen only once at the falls. Length six inches, 

 body nearly cylindrical. Mouth rather inferior, lips 

 thick and somewhat gristly. Iris silvery. Scales 

 pretty large. Fins whitish, the dorsal and caudal a 

 little redish. Pectoral fins elliptical with 16 rays. 

 Tail 20. Dorsal fin trapezoidal, opposed to the ab- 

 dominal, the first ray shorter. Anal elliptical obtuse. 

 Vulgar names Black Sucker and Blue Sucker. 



62d Species. Rough-head Sucker, Catostomus 

 fasciolaris. Catostomus fascie. 



Diameter one sixth of the length: brown above, 

 white be- [II. 305] neath, sides with small transversal 

 black lines : head sloping, tuberculated above, snout 

 obtuse: dorsal fin longitudinal reaching the end of 

 the anal fin, lateral line straight. 



I have not seen this species, but describe it from a 

 drawing of Mr. Audubon. It is found in the lower 

 part of the Ohio. Vulgar names Rough-head Sucker, 

 Pike Sucker, Striped vSucker. Length about eight 

 inches, body cylindrical tapering behind. 



[5p] Eyes small, mouth beneath. Lower fins 

 trapezoidal, about twenty transversal lines. A 

 doubtful species, perhaps an Hydrargyrus, but the 

 mouth is like that of the Sucker. 



63d Species, Red-tail Sucker, Catostomus ery- 

 thrurus. Catostome rougequeue. 



Diameter one fifth of the length: rufous brown 



