122 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



Lateral line well developed, straightisli. Fius generally rather small. 

 First ray of dorsal usually about midway of body, its rays few, 9-12 

 in number. Yeutrals inserted rather under posterior part of dorsal, 

 tlieir rays 10 or 9. Anal short and high, with 7 developed rays. Cau- 

 dal rather shallow-emarginate. Pectorals well developed. Air-blad- 

 der with two chambers. Size rather small. Species numerous in the 

 Rocky Mountain region, (-ay, all ; (xrrio'^^ bone.) 



* Scales moderate, 80-85 in tlie lateral line. 



a. Scales subequal over the bodj^, not reduced forwards. 



123. P. j>Sc5>ciMS (Baird & Girard) Jordan. 



Body rather stout, subfusiform. Head slender, rather short, 4'^ in 

 length. Eye 5 in head. Ventrals reaching nearly to vent. Scales 

 small, scarcely crowded anteriorly, 80 in the lateral line, 20-30 in a 

 cross-series. Depth 4i in length. Dorsal midway between snout and 

 ux)per caudal rays. Caudal short, emarginate. Color dark brown, 

 faintly mottled ; sides with orange in the males. {Girard.) Lake Guz- 

 man, Mexico. 



{Catostomm pleleius Baird & Girard, Proc. Acad. Nat. Sci. Pliila. 1854, 28: Catosto- 

 mus 2)lbhej us Giinthev, vii, 15; Jordan,!, c. 184.) 



124. P. deapEiiBfius Cope. 



"The dorsal outline is arched, the head flat above, not elevated behiud 

 and much depressed on the muzzle. The muzzle is wide and does not 

 project beyond the upper lip, which is appressed to its lower face and 

 bears four rows of warts; its smooth commissural part is narrow. On 

 the lower lip the tubercles advance nearly to the commissure ; this lip 

 is deeply emarginate posteriorly. The eye enters the length of the head 

 5 times, 2i times measuring the muzzle, and twice the interorbital re- 

 gion. Head 4§ times in length to end of caudal basal scales. Scales iu 

 30 longitudinal series, between dorsal and ventral fins. Ventrals re- 

 markably short, extending little more than half way to vent, originat- 

 ing under posterior third of dorsal. Pectorals well separated. Isthmus 

 wide. Color above blackish, with a strong inferior marginal shade on 

 the lower part of the sides, and the lighter tint above ; a brown spot 

 just above axilla is cut oft' from it by a band of the yellow color which 

 covers the belly and head below." (Cope.) Probably from Green River. 



(Al'momm delph'mus Cope, Hay den's Gcol. Surv. Wyom. Terr. 1872, 436.) 



125. P. bardMS Cope. 



This species is distinguished by its very short head and marked col- 

 oration, resembling in that respect the C. (juzmaniensis of Girard ; with 



