42 SCIENCE SKETCHES. 
Europe very similar species are the Scotch Ven- 
dace (Coregonus vandesius) and the Scandinavian 
Lok-Sild (lake herring), as well as others less 
perfectly known. 
The Tullibee, or ‘“‘ Mongrel White-fish” (Corego- 
nus tullibee), has a deep body, like the shad, with 
the large mouth of the ciscoes. Fishermen think 
it a hybrid between Coregonus clupetformis and C. 
artedt. I(t is found in the Great Lake region and 
northward, and very little is known of its habits. 
A similar species (Coregonus cyprinoides) is re- 
corded from Siberia,—a region which is pecu- 
liarly suited for the growth of the Coregonz, but in 
which the species have never received much study. 
Allied to the Coregoni is Plecoglossus altivelis, a 
small fish of the waters of Japan and Formosa. It 
has small, compressed, serrated, movable teeth in 
the jaws. This is said to be an annual fish, the life 
of each individual ceasing at the end of the season 
of reproduction. 
Another little-known form, intermediate between 
the white-fish and the salmon, is Brachymystax 
lenock, a large fish of the mountain streams of 
Siberia. Only the skins brought home by Pallas 
about a century ago seem to be known as yet. Ac- 
cording to Pallas, it sometimes reaches a weight of 
eighty pounds. 
Still another genus, intermediate between the 
white-fish and the salmon, is Stexodus, distin- 
guished by its elongate body, feeble teeth, and 
projecting lower jaw. The Inconnu, or Mackenzie 
River Salmon (Stenodus mackenziz) belongs to this 
genus. It reaches a weight of twenty pounds or 
