FISHES-CYPRINIDAE-LEUCOSOMUS PALLIDUS. 
251 
The color is uniform greyish brown above, silvery along the middle of the flank, and dull 
yellowish beneath ; the fins being of a greyish olive tint. 
List of specimens. 
Catal. 
No. 
Cor’g No. 
of teeth. 
Mo of 
spec. 
Age. 
Locality. 
When col¬ 
lected. 
Whence obtained. 
Nature of 
specimen. 
Collected by— 
158 
2733 
2 
Milk river, Upp. Mo.. 
1853 
Gov. I. I. Stevens_ 
Alcoholic.. 
Dr. Geo. Suckle 
159 
2734 
12 
Young 
Lit. Muddy riv. Up. Mo 
1853 
ICO 
18 
1853 
2. LEUCOSOMUS PALLIDUS, Gf r d. 
Plate LXI, Figs. 6 —10. (By error: Leucosomus macrocephalus .) 
Spec. Char. —Head moderate sized, rather elongated, entering four times and a-half in the total length. Snout eub-conical 
and tapering. Eye moderate; its diameter being contained fire times in the length of the side of the head. Gape of mouth 
somewhat oblique ; posterior extremity of the maxillary extending to a vertical line intersecting the anterior rim of the pupil. 
Anterior margin of dorsal fin nearer the insertion of the caudal than the extremity of the snout. Insertion of ventrals situated 
somewhat in advance of the anterior edge of the dorsal. Greyish brown above, yellowish white beneath; a black spot at the 
base of the caudal and anterior edge of the dorsal fin. 
Svn. — Leucosomus pallidas, Grd. in Proc. Acad. Nat. Sc. f'hilad. VIII, 1856, 190. 
This species has the same general physiognomy as L. disbimilis. The scales of the back are 
likewise a good deal smaller than on the flanks, but in totum they are larger than in the pre¬ 
ceding species. The origin of the ventrals is likewise situated in advance of the anterior margin 
of the dorsal. The caudal fin is not so deeply furcated as in L. dissimilis. The dorsal and 
anal fins are deeper than long ; they are of but moderate development, as well as the ventrals 
and the pectorals ; the tips of the ventrals scarcely approximating the vent. 
D 1, 8 + 1; A 2, 8 + 1 ; C 7, 1, 9, 8, 1, 8 ; V 1, 8 ; P 17. 
The scales moderate sized, somewhat smaller on the back than on the sides ; sub-circular in 
outline, with radiating furrows upon their posterior section only. 
The dorsal region is greyish brown, the ventral region yellowish white. A black spot may 
be observed at the base of the caudal, and another upon the anterior margin of the dorsal. 
References to the figures. —Plate LXI, fig. 6, represents Leucosomus pallidus, size of life. 
Fig. 7 is a section of the body across the line of greatest depth. Fig. 8, a scale of the dorsal 
region. Fig. 9, a scale from the lateral line. Fig. 10, a scale from the abdominal region. 
List of specimens. 
Catal. 
No. of 
Age. 
Locality. 
When col- 
Whence obtained. 
Orig’l 
Nature of 
Collected by— 
No 
spec. 
lected. 
No. 
specimen. 
157 
8 
A.&Y. 
Antelope creek, Ark. 
1853 
Lt. A. W. Whipple .... 
VIII. 
Alcoholic. 
Dr. C. B. Kennerly. 
