82 Annals of the Carnegie Museum. 



to that of anal ; anal short, its base 1 1 in body, its height equal to that of 

 dorsal; caudal deeply emarginate; the ventrals behind the middle of the 

 dorsal, and as long as its height. Lateral line straight, ascending ante- 

 riorly, and slightly dorsal in position. Scales are small, their breadth about 

 one-fourth the eye diameter ; oval anteriorly but becoming much elongated, 

 2 to 2 J^ times their breadth, posteriorly ; very small between the pectorals 

 and largest dorsally. Body dark above, light below, with numerous dark 

 brown or black spots, 4 or 5 scales in extent, above and on the sides a little 

 below the lateral line. Dorsal, anal, and ventral fins dusky on the distal 

 half, the caudal edged with dark, the adipose with 4 to 7 spots similar 

 to those on the body, and the pectorals uncolored. 



According to Pallas, this singular fish, intermediate between a \\'hite- 

 fish and a Trout, reaches the weight of 60 to 80 pounds. 



Stenodus leucichthys (Giildenstadt). {Salmo velvia Pallas.) 

 (Plate XXI.) 

 This Siberian species was not taken at Irkutsk by Professor Abbott, 

 but specimens were obtained from the Volga River at Sammara in Russia. 

 In view of the interest attaching to this interesting fish, intermediate 

 between the Trout and the Vendace or Lake Herring, we here present a 

 figure of it. 



2. Coregonus pidschian (Pallas). (Plate XXII.) 



Salmo pidschian Pallas, Reise, III, 1776, 705 (River Obi). — Gmelin, Syst. Nat., 



1788, 1377 (after Pallas). 

 Salmo shokur Gmeltn, Syst. Nat. 1788, 1378 (River Obi). 

 Salmo polciir Pallas, Zoogr. Ross. -As., Ill, 1811, 400 (River Obi). 

 Coregonus polcur Gunther, Cat., VI, 1866, 178 (after Pallas). — Smith, Salmoniden, 



1886, 271, Tab. XVIII, no. 412, 428, fig. 99-100 (Yenesei R. to Nikandrovei 



and Mirna; good figures of head). 



One specimen 315 mm. in length without caudal. 



Head 5/4 in length, without caudal; depth 4, at base of caudal 2^ in 

 head. Eye 4J'2 in head, ly'z in snout, i^^ in interorbital space. B. 10. 

 D. 12 (developed rays). A. 14. Scales 1 1-90-9; gill-rakers 22. 



Body compressed, the ventral outline convex, the dorsal less so. Head 

 small, strongly arched between snout and interorbital space, the latter 

 rounded from eye to eye. Snout slightly narrowed, projecting a third of 

 its length beyond the very small ventral mouth, measuring it from the 

 posterior edge of the adipose eyelid to its tip. Premaxillaries forming a 

 flat, obliquely-placed spiral plate, a little broader than high, between the 



