OATOSTOMIDiE. — CIX. 311 



jj. MoutK larger, sub-terminal, protractile forwards (species 

 of larger size, dusky colors, with lower dorsal). 



ICHTHYOBUS, 10. 



ii. Pharyngeal bones strong ; the teeth Comparatively coarse 

 and large, increasing in size downwards; dorsal tin 

 moderately elevated ; mouth inferior. Bubaljchthys, 11. 



/. QUASSILABIA, Jordan & Brayton. Hare Lip Suckers. 

 [Lagochila^ J. & B., preoccupied.) 



1. d. lacena, Jor. & Brayt. Hare Lip Sucker. Split 

 Mouth Sucker. Head short, 4f in body, with length- 

 ened, non-protractile fleshy snout; body elongate, its 

 depth about 5 in length; eye medium, set far back, the 

 oporcle smr.U; fins not large; scales, etc., as in Mt/xos- 

 toma; D. I, 12; A. I, 7; V. 9; lat. 1. 45. Tennessee 

 and Cumberland Rivers; a most remarkable species, 

 bearin"^ the same relation to the other Catostomidoe^ that 

 Exoglossum does to the other G yprinidm. It seems to 

 possess roal affinities with Exoglossum. 



2. PLACOPHARYNX, Cope. Placopharyxx. 



1. P. caninatus, Cope. Cope's Sucker. Resembles 



M. anisura^ but the lips and pharyngeal bones quite 



different; eye 4|- in head; head 4 in length; depth 3f • 



head strongly ridged above; pharyngeal bones very 



heavy, the lower 7 to 12 teeth on each side very large, 



scarcely compressed; truncate, irregularly placed; D. I, 



14; A. I, 7; lat. 1. 41; head with a median ridge on top; 

 a large, coarse species similar in general characters to 



Myxostoma^ but with the physiognomy approachuig 



somewhat that of Ichthyohus. It is probably common 



in the Western streams, although it v;as not noticed 



until 1870. I have specimens from the Illinois, Wabash, 



Detroit, Falls of the Ohio and the Scioto, and French 



Broad. 



