The Humpback Whitefish 



Head 5; depth 3; eye 4 to 5; D. n; A. n; scales 8-74; 

 vertebrae 59; gillrakers usually 10+17 to 19; maxillary 4. Body 

 oblong, compressed, always more or less elevated, becoming 

 notably so in the adult; head small and short, the snout blunt- 

 ish and obliquely truncated, the tip on the level or lower edge 

 of pupil; width of preorbital less than half that of pupil; maxil- 

 lary reaching past front of orbit; gillrakers moderate, about 2 in 

 eye. Colour, olivaceous above, the sides white, but not silvery; 

 lower fins sometimes dusky. 



Humpback Whitefish 



Coregonus nelsonii Bean 



This whitefish occurs in Alaska from Bristol Bay northward, 

 where it is said to be not uncommon. According to Dr. Bean, 

 Nelson's whitefish has long been known from Alaska, but it has 

 been confounded with a Siberian species, C. syrok, from which 

 it is really very different. The Russian name is Korabati, while 

 the Tenneh tribes of the Yukon call it Kolokuh. Dr. Dall speaks 

 of it as a common species, and says it is rather bony, inferior in 

 flavour, and that it is generally used for dog-food except in times of 

 scarcity. 



Head 5; depth 4; maxillary 4; D. 12; A. 12; scales 10-88-8; 

 gillrakers 26 in number, their length 2 in eye. Allied to C. clu- 

 peiformis, but distinguished by its arched and compressed back. 

 Colour, plain whitish. 



GENUS ARGYROSOMUS AGASSIZ 

 The Lake Herrings or Ciscoes 



This genus is very close to Coregonus, from which it differs 

 in the larger mouth, and more produced jaws, the premaxillaries 

 being placed nearly horizontally, and the lower jaw projecting 

 decidedly beyond them. The gillrakers are very long and slender, 

 with about 30 on the lower limb of the first arch; vertebrae 55. 

 These characters are associated with greater voracity, and, in general, 

 greater activity of the species. 



The species of Argyrosomus are numerous in northern parts of 



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