The Pacific Salmon 



to 40 pounds. Its large size and comparative abundance render 

 the inconnu of considerable commercial importance, especially in 

 the Yukon since the great development of the gold-fields of that 

 region. Little or nothing is known of the habits of this species. 



Head 4|; eye 6; D. 12; A. 14; scales 100;. gillrakers 7+17. 

 Eye less than snout, nearly equalling the narrow interorbital ; 

 maxillary reaching the vertical of posterior edge of pupil, its 

 length very slightly more than ^ head; supplemental bone long 

 and narrow, nearly as wide as the maxillary, the anterior end 

 notched, the angle above the notch sharply pointed, the lower 

 angle bluntly rounded; the gillraker in the angle very stiff and 

 bony. 



GENUS ONCORHYNCHUS SUCKLEY 

 The Pacific Salmon 



Body rather long, subfusiform, and compressed; mouth wide, 

 the maxillary long, lanceolate, usually extending beyond the eye; 

 jaws with moderate teeth, which become in the adult male 

 enormously enlarged in front during the spawning season; vomer 

 long and narrow, flat, with a series of teeth both on the head 

 and the shaft, the latter series comparatively short and weak; 

 palatines with a series of teeth ; tongue with a marginal series on 

 each side; teeth on vomer and tongue often lost with age; no 

 teeth on hyoid bone; anal fin comparatively long, of 14 to 20 

 rays; pyloric coeca very numerous; gillrakers numerous; ova large 

 and comparatively few. Sexual peculiarities very strongly devel- 

 oped, the snout in the adult males greatly distorted during the 

 breeding season, the premaxillaries prolonged, hooking over the 

 lower jaw, which in turn is greatly elongate and somewhat hooked 

 at the tip; the body becomes deep and compressed, a fleshy hump 

 is developed before the dorsal fin, and the scales become em- 

 bedded in the flesh, and the flesh, which is red and rich in the 

 spring, becomes dry and poor. 



The American species of this genus, 5 in number, are mostly 

 salmon of large size, ascending the rivers tributary to the North 

 Pacific in America and Asia. The genus is very close to Salmo, 

 differing chiefly in the increased number of anal rays. 



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