182 REPORT OF STATE GEOJ.OGIST. 



and has no supplemental bone. From the white-fishes, again they may 

 be distinguished by the absence of an adipose fin. 



Pharyngeal bones with a single row of numerous teeth, which are ar- 

 ranged like the teeth of a comb. Maxillaries forming the hinder part of 

 the margin of the upper jaw. Suckers and river carps. 



Catostomiche, p. 182. 



Pharyngeal bones with one to three rows of teeth, of which not more 

 than seveu are found in the main row, and fewer in the others, if present; 

 margin of the upper jaw formed wholly by the preraaxillaries. Tooth- 

 less rainn.)ws and pond carps. Cyprinidce, p. 197. 



Family CATOSTOMID.E. 

 SUCKERS, CARPS, AND BUFFALO FISHES. 



Body usually somewhat compressed. Mouth moderate ox small ; tooth, 

 less ; its upper margin formed by the premaxiliaries in front, by the 

 maxillaries behind. Teeth of the pharyngeals numerous, in a s-ingle row, 

 resembling the teeth of a comb. Gill membranes united to the isthmus. 

 Ventral fins with about ten rays. Pectorals placed low on the body. 



In many of the genera of this family there is present a fontanelle in the 

 upper surface of the head. It may be discovered by thrusting into it the 

 point of some sharp instrument. 



ANALYSrS OF THE GENERA OF CATOSTOMID.E. 



A. Air bladder in three pirts. Fontanelle present. 



a. Upper lip protractile; lower lip not split into two distinct 

 lobes, 

 b. Mouth of usual sucker-like form. 



c. Lower teeth of the pharyngeals compressed. 



Moxostoma, p. 183. 



cc. Lower teeth of the pharyngeals much enlarged, nearly 



cylindrical, and truncated. Placopharynx, p 186. 



bb. Mouth modified. Lower lip split into two depending 



lateral lobes. Lagochila, p. 186. 



AA. Air bladder in two parts. 



d. Fontanelle present ; the body considerably compressed, 

 e. Dorsal fin short; its rays ten to eighteen. 



Catostomus, p. 187. 

 ee. Dorsal rays from twenty-three to thirty. Scales forty- 

 five, or fewer. 



Ictiohis, p. 192. 

 dd. Fontanelle not present. Body elongate, little compressed. 

 Dorsal rays about thirty. Scale; about fifty-five. 



Cycleptus, p. 196. 



