FISHES—CYPRINIDAE—MONTANA TRISTIS. 
277 
latter fin is nearer the fork of the caudal than the isthmus. The caudal fin is nearly 
equal to the head in length. The origin of the ventrals is slightly nearer the extremity 
of the snout than the insertion of the caudal; they are rounded posteriorly, their tips over¬ 
lapping the vent, and reaching at the same time the anterior edge of the anal. The pectorals 
are slender, their extremities not extending as far as the insertion of the ventrals. The rays 
are as follows: 
D 2, 8 + 1; A 2, 8 + 1; C 7, 1, 9, 8, 1, 8 ; V 1, 8 ; P 14. 
The scales are rather large, and the furrows of their posterior section quite numerous. The 
lateral line is deflexed upon the middle of the abdomen, and somewhat nearer the insertion of 
the ventrals than the base of the dorsal. 
The dorsal region is reddish brown ; the sides and abdomen being of a metallic yellow or 
white tint. The middle of the flanks exhibit sometimes an indistinct, or rather diffused 
greyish silvery, occasionally blackish, hand or streak. 
Beferences to the figures .—Plate LIX, fig. 16, represents very imperfectly and incorrectly 
Moniana frigidct , size of life. Fig. 17 is a section of the body taken upon the line of greatest 
depth. Fig. 18, a dorsal scale. Fig. 19, a scale from the lateral line. Fig. 20, a scale from 
the abdominal region. 
List of specimens. 
Catal. 
No. 
No. of 
spec. 
Age. 
Locality. 
When 
collected. 
Whence obtained. 
Orig. 
No. 
Nature of 
specimen. 
Collected by— 
99 
i 
Adult. 
Rio Frio, trib. of Rio Nueces, Tex. 
1853 
Lt.A.W. Whipple. 
21 
Alcoholic. 
Dr. C. B. Kennedy. 
7. MONIANA TRISTIS, Grd. 
Spec. Char. —Body elongated, sub-fusiform. Peduncle of tail long and slender. Head constituting the fifth of the length. 
Snout rounded and rather abbreviated ; jaws equal. Posterior extremity of maxillar bone extending to a vertical line drawn 
behind the nostrils. Eye large and circular ; its diameter entering about three times and a half in the length of the side of the 
head. Anterior margin of dorsal fin somewhat nearer the extremity of the snout than the insertion of the caudal. Vertical 
fins well developed. Reddish brown, lighter beneath than above, with a lateral dark streak. 
Syn. —Moniana tristis, Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 201. 
A slender and graceful species, sub-fusiform in profile, though the hack, properly so called, is 
rather arched. The peduncle of the tail is long and of nearly uniform depth. The head 
constitutes about the fifth of the length. The vertical fins are well developed. The caudal is 
longer than the head, deeply crescent-shaped upon its posterior margin. The dorsal and anal 
are much higher else deeper than long ; the former slightly linear, the latter slightly concave, 
upon their external edge, the anterior margin of the anal being equidistant between the 
isthmus and the concavity of the caudal. The horizontal fins are of moderate development; 
the origin of the ventrals is nearer the tip of the snout than the insertion of the caudal; these 
fins are posteriorly sub-truncated, slightly rounded off, and when stretched backwards they 
reach the vent. The pectorals are sub-ovate in their outline, their tips not extending quite to 
the insertion of the ventrals. The formula of the rays is : 
D 2, 8 + 1 ; A 2, 7 + 1; C 6, 1, 9, 8, 1, 7; V 1, 8; P 15. 
The scales are of moderate development; eleven rows of them may he counted upon the line 
