648 



FISHES. 



extremely minute and deciduous. Dorsal fin of moderate length ; 

 caudal deeply forked. Ova small. 



Fig. 293. — Coregoniis oxyrhynchus. 



The majority of the species, of which more than forty are 

 known, are lacustrine species ; and comparatively few are 



Fig. 294. — Head of Coregonus oxyrlayuchus. 



subject to periodical migrations to the sea, like Salmo. They 

 are confined to the northern parts of temperate Europe, Asia, 

 and North America. Their distribution is local, but some- 

 times three and more species are found in the same lake. 

 They abound in every lake and river of the northern parts of 

 North America, and are known by the name of " White-fish." 



