31. CYPRINID^ — GILA. 227 



depth Of. D. S; A. 7 5 scales 17-90-9; teeth 2, 5-4, 2. L. 30 inches. 

 Sacramento Kiver, with P. oregonensis, but less common in the markets. 

 (Jordan & Gilbert, Proc. V. 8. Nat. Mus. 1881.) 



358. P. luciiis Grd.— CoZomrfo " Fike". 



Body .slender, elongate, with lonjj, slender, depressed head ; the form 

 and general appearance being that of Ft. oregonensis. Maxillary reaching 

 past anterior margin of the eye. Eye small, 2^ in snout, 7 in head. 

 Lateral line very strongly decurved. Fins low, the dorsal evidently 

 behind ventrals. Scales very small. Coloration plain, darker above. 

 Head 3i; depth 5^. D.9; A. 9; Lat. 1. 104; teeth 2, 4-5, 2. Colorado 

 River; abundant. 



(Girard, Proc. Acad. Nat. .Sci. Pliila. Irioi), 209, and IJ. S. Mex. Bound. Surv. Iclith. 

 65.) 



101.— OIL. A Baird 6c Girard. 

 (Baird & Girard, Proc. Acad. Nat. 8ci. Pliihi. 18.5:], 3tiS: typo (rila rohmta B. & G.) 



Body elongate, little compressed, the back arched, especially in the 

 adult; the caudal peduncle typically extremely long, slender, con- 

 tracted, much narrower than the base of the caudal tin, which is widely 

 forked, with its basal fulcra very much developed. Head in typical spe- 

 cies broad, depressed, its profile concave. Mouth large, horizontal, and 

 overlapped by the broad snout. Dorsal tin behind the middle of the 

 body, slightly behind ventrals. Anal basis short. Intestinal canal short . 

 Scales very small, little imbricated, sometimes scarcely imbricate at ;ill, 

 longer than deep, especially posteriorly, '^o barbel. Pseudobranchife 

 present. Teeth 2, 5-4, 2, close set, compressed and hooked, without 

 grinding surface. Vertebric about 4G (5 or more than usnal in i^qualhis). 

 Intestinal canal short; peritoneum dusky. Species of large size, the 

 typical form remarkably unlike the usual Cyprinoid type, but varying 

 through a series of intermediate forms directly into SqualiuSj so that 

 the genus is hardly distinguishable by any definite technical character, 

 unless the greater luimber of vertebrae be found constant. {Gila, the 

 name of the river where the typical species was first obtained.) 



* Head depressed anteriorly, the occipital region high, so that the proiilo is notably 

 concave. 



.359. ii. <>lcg:aiis B. & G. 



The extreme species of this type. Body elongate, somewhat com- 

 pressed, the region before the dorsal elevated, forming a sort of liump, 

 the dorsal fin inserted on the downward slope of the back, so that its 

 base is quite oblique. Caudal peduncle extremely long and slender, as 



