PLECTOSPONDYLI— GYPEINIDAE— HYBOPSIS SCYLLA. 



655 



line of tubules is imperfect in all the specimens ; often only represented by 

 a short series in front of the dorsal fin. In larger specimens, it is better 

 developed, and in still larger it may be complete, a point which remains as 

 yet uncertain. In the smaller specimens of Myloleucus parovamis, the series 

 is imperfect for a short distance in front of the caudal fin, while it is com- 

 plete in adults. The same has been observed in the Hypsilepis analostanus, 



13 



Girard. Scales small, m. The dorsal fin originates a little in front of a 



6 



line drawn from the base of the first ventral ray. The pectorals do not 

 reach the ventrals, while the latter attain the vent. Radii : D. I. 9 ; A. I. 8 ; 

 V. 8. 



The depth is one-fourth the length less that of the caudal fin, and the 

 length of the head enters the same 3.66 times. Orbit 3.3 times in length of 

 head, 1.2 times in interorbital width ; longer than muzzle. Preorbital bone 

 trapezoid. Total length, m .047 ; length to basis of dorsal, ra .0215 ; of head, 

 m .011 ; width at pterotics, m .005. 



There is a narrow leaden line from the pterotic region to the base of 

 the caudal, below which the color is yellowish and above brownish, all 

 dusted with black points. Cheeks silvery. Fins dusky. 



Numerous specimens were taken at Provo by Dr. II. C. Yarrow and II. 

 W. Henshaw, and at Gunnison (No. 668) by F.. Klett and H. W. Henshaw. 



The specimens taken at Gunnison were found in a small ditch having 

 no visible inlet or outlet, situated about one mile from the Sevier River. 

 The water in this ditch was stagnant and alkaline, yet it fairly teemed with 

 these little fishes. 



No. 



Locality. 



Date. 



Collector. 



666, 2 



66S 

 4SBB 





Aug., 1S72 

 ..do 



Dr. H. C. Yarrow and H. W. 



Henshaw. 

 Francis Klett. 

 H. W. Henshaw. 





do 



Sept., 1S72 





HYBOrSIS SCYLLA, Cope. 

 Hybopsis scylla, Cope, Anu. Rep. U. S. Geo!. Surv. iSTO, 43S (var.). 



Specimens agreeing in form of body, fin radii, squamation, and color 

 with this species, but with a relatively longer head and larger orbit. Scales, 



