PLECTOSPONDYLI— CYPRINIDAE— GILA ROBUSTA. 



663 



GILA NIGRA, Cope, s^. nov. 



Plate XXX, Figs. 3, 3a. 



This species, which is represented by a number of specimens in the 

 collection of the survey, resembles those last enumerated, and differs from 

 the G. pandora in the considerably more numerous scales ; from the G. egre- 

 gia it differs in the relatively larger head, which enters the length minus 

 the caudal fin only three and one-half times, instead of four times. The 



21 20 20 



dental series is found to be in several specimens 4.2-2.5. Scales, ij, w, 15, in 



12 11 11 



three specimens. General shape fusiform ; profile gradually descending, 

 then decurved to the upper lip, which overhangs the lower by a little ; 

 mouth slightly descending. Teeth, 4.2-2.5 ; isthmus rather wide. Eye 

 not large ; in adults six times in length of head, 1.75 times in muzzle, and 

 twice in interorbital width. The fins are all rather small, including the cau- 

 dal ; the pectorals reach 0.6 the distance to the ventrals, and the latter 0.6 the 

 distance to the anal. Radii : D. I. 8 ; A. I. 8 ; V. 9. Least depth of caudal 

 peduncle 2.6 times into greatest depth (in front of dorsal fin), which enters 

 the length without the caudal fin four times. Total length, m .235 (7 \ 

 inches) ; length to basis of first dorsal ray, m .113 ; length to basis of caudal 

 fin, m .200. 



General color black. Lower surfaces olive. 



No. 



Locality. 



Date. 



Collector. 



204 

 1019 





July, 1874 

 Oct., 1874 



Dr. J. T. Rothrock. 

 H. W. Hen:haw. 



San Carlos, Ariz 



GILA ROBUSTA, Bel. & Gir. 



Gila robusta, Bd. & Gir., Proc. Acad. Nat. Sci. Phila., vi, 1S53, 369. — lid., Sitgreave's 

 Exp. Zuni & Col. Riv., 1853, Fishes, 148, pi. 1, f. I.—Iid., P. R. R, Rep., x, 

 1857, Fishes, 2S5. 



A comparison of two good specimens with Baird and Girard's descrip- 

 tion reveals some trifling differences with regard to number of radii. Speci- 

 men No. 504, from Zuni River. New Mexico, has the following formula : 



