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 clupeiformis and C. 

 artedi. It 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 Coregoni, 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 Stenodus, distin- 

 guished by its elongate body, feeble teeth, and 

 projecting lower jaw. The Inconnu, or Mackenzie 

 River Salmon {Stcnodus mackenzii) belongs to this 

 genus. It reaches a weight of twenty pounds or 



