Salmonide _ 67 
prognathus). Argyrosomus lucidus is abundant in Great Bear 
Lake. In Alaska and Siberia are still other species of the cisco 
type (Argyrosomus lauretta, A. pusillus, A. alascanus); and in 
Europe very similar species are the Scotch vendace (Argyrosomus 
vandestus) and the Scandinavian Lok-Sild (lake herring), as 
well as others less perfectly known. 
The Tullibee, or ‘mongrel whitefish”? (Argyrosomus tullibee), 
has a deep body, like the shad, with the large mouth of the 
ciscoes. It is found in the Great Lake region and northward, 
and very little is known of its habits. A similar species (Argy- 
rosomus cyprinoides) is recorded from Siberia—a region which 
is peculiarly suited for the growth of the Coregoni, but in wabiclt 
the species have never received much study. 
Brachymystax and Stenodus, the Inconnus.—Another little- 
known form, intermediate between the whitefish and the salmon, 
Fig. 52.—Inconnu, Stenodus mackenziei (Richardson). Nulato, Alaska. 
is Brachymystax lenock, a large fish of the mountain streams of 
Siberia. Only the skins brought home by Pallas a century ago 
are yet known. According to Pallas, it sometimes reaches a 
weight of eighty pounds. 
Still another genus, intermediate between the whitefish and 
the salmon, is Stenodus, distinguished by its elongate body, 
feeble teeth, and projecting lower jaw. The Inconnu, or Mac- 
kenzie River salmon, known on the Yukon as ‘“‘charr’”’ (Stenodus 
mackenziet), belongs to this genus. It reaches a weight of twenty 
pounds or more, and in the far north is a food-fish of good 
quality. It runs in the Yukon as far as White Horse Rapids. 
Not much is recorded of its habits, and few specimens exist in 
