320 



U. S. P. E, B. EXP. AND SUEVEYS ZOOLOGY GENERAL EEPOET. 



Specimens of this species were collected by Dr. Greo. Suckley at the Falls of the Missouri 

 river, Rocky mountains. 



References to the figures. Plate LXXII, fig. 1, represents S alar leivisi, two-thirds the size of 

 life. Fig. 2, a scale from the dorsal region. Fig. 3, a scale from the lateral line. Fig. 4, a 

 scale from the abdominal region. Figs. 2 4 are magnified views. 



List of specimens. 



2. SALAR VIRGIN ALIS, Grd. 

 PLATE LXXIII, FIGS. 14. 



SPEC. CHAR. Body sub-fusiform in profile, otherwise compressed ; head comprised about four times in the total length, the 

 caudal fin excluded ; jaws sub-equal ; posterior extremity of maxillary extending to a vertical line intersecting the posterior rim 

 of the orbit. Anterior margin of dorsal nearer the extremity of the snout than the insertion of the caudal fin. Greyish brown 

 above, with a purplish reflection and sub-circular black spots ; beneath olivaceous, unicolor. 



SYN. Salar virginalis, GRD. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 220. Salmo virginalis, GRD. Mss. 



The body, which is sub-fusiform when seen in profile, is very much compressed ; its greatest 

 depth, anterior to the dorsal fin, enters five times and a quarter in the total length, whilst the 

 least depth, on the peduncle of the tail, enters about eleven times in that same length. 



The head is sub-conical and proportionally well developed, constituting the fourth of the 

 length from the tip of the snout to the insertion of the caudal fin. The mouth is moderately 

 cleft, for, the posterior extremity of the maxillary reaches a vertical line drawn immediately 

 posterior to the orbit. The teeth are small and acute, a little larger, as usual, on the dentary 

 and the tongue than on other bones. They become very exiguous along the posterior portion 

 of the maxillary. The snout is obtusely rounded and the jaws sub-equal, with a proclivity of 

 the upper jaw to protrude beyond the lower. The eye is large, sub-circular, its diameter 

 being contained four times and a half in the length of the side of the head, a little over once in 

 advance of the anterior rim of the orbit. The nostrils are large, situated towards the upper 

 surface of the head and nearer the eye than the tip of the snout. The opercle is elevated, 

 rather narrow, a little wider beneath than above, slightly oblique, whilst the sub-opercle, 

 moderate in development, is rounded upon its free margin. The branchiostegals are nine on 

 either side. 



The anterior margin of the dorsal fin is a little nearer the extremity of the snout than the 

 insertion of the caudal fin. The fin itself is higher than long, its upper margin being sub- 

 convex, and its posterior margin half the height of the anterior. The adipose is very slender, 

 its tip being even with the tips of the middle rays of che anal. The caudal is sub-crescentic 

 upon its margin ; it is contained seven times in the total length. The anal is sub-concave 



