FISHES — CYPRINIDAE — MONIANA TRISTIS. 



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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 hrown ; the sides and abdomen being of a metallic yellow or 

 white tint. The middle of the flanks exhibit sometimes an indistinct, or rather diifused 

 greyish silvery, occasionally blackish, band or streak. 



Eeferences to the figures. — Plate LIX, fig. 16, represents very imperfectly and incorrectly 

 Moniana frigida, 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. 



7. MONIANA TEISTIS, 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 

 behmd 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 tlie 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 back, 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 -f 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 be counted upon the line 



