886 | FISHES—SALMONIDA. 
Genus 50. ONCORHYNCHUS. Suckley. 
Oncorhynchus, SUCKLEY, Ann. Lyc. Nat. Hist. N. Y., 1871, 312. 
Type, Salmo scouleri, Rich., Suckley, = Salmo kisutch, Walbaum, not Salmo scouleri, 
Richardson, which is Salmo gorbuscha, Walbaum. 
Etymology, ogkos, hook; rugkos, snout. 
Body elongate, subfuciform or compressed ; mouth wide, the maxillary long, lanceo- 
late, usually extending beyond the eye; jaws with moderate teeth, which become in the 
adult male enormously enlarged in front; vomer long and narrow, flat, with a series of 
teeth both on the head and the shaft, the latter series comparatively short and weak ; 
palatine with teeth ; tongue with a marginal series on each side; teeth on vomer and 
tongue often lost with age ; no teeth on the hyoid bone; branchiostegals more or less 
increased in number; scales moderate or small; dorsal fin moderate; anal fin compara- 
tively elongate, of 14-20 rays; pyloric appendages in increased number: gill-rakers . 
rather numerous; ova large; sexual peculiarities (in typical species) very strongly 
developed ; the snout in the adult males greatly distorted ; the premaxillaries prolonged, 
hooking over the lower jaw, which in turn is greatly prolonged and somewhat hooked 
at tip; the teeth of these bones also greatly enlarged; a fleshy hump is developed 
before the dorsal fin, and the scales of the back become imbedded in the flesh. Salmon, 
mostly of large s'ze, ascending the rivers tributary to the North Pacific in North 
America and Asia, now being introduced into Atlantic waters. The genus includes the 
largest of the Salmon family, and the noblest of our food fishes. One of the five known 
species has been introduced into various eastern streams and lakes, 
99. OXCORHYNCHUS CHOUICHA (Walbaum) Jordan and Gilbert. 
Quinnat Salmon; Hing Salmon; Chouicha ; Columbia Salmon; 
Chimnmock Salmon; Saw-kwey; Spring Salmon; Sacramento 
Salmon. 
Salmon ishawytscha (Chouicha), WaLBAUM, Aitedi Pisc., 1792, —. 
Salmo orientalis, PALLAS, Zoogr. Rossc-Asiat., ili, 1811. 
Salmo quinnat, RICHARDSON, Fauna Bor.-Amer., iii, 1836, 319, and of most late writers. 
Oncorhynchus quinnat, GUNTHER, Cat. Fishes Brit. Mus. vi, 158—JORDAN, Proc. U.S. 
Nat. Mus., i, 69. 
Salmo quinnat, confluentus, and argyreus, SUCKLEY, Monogr. Salmo., 105, 109, 110. 
Description.—Color dusky above, often tinged with olivaceous or bluish; sides and 
below silvery ; head dark slaty, with metallic lustre, usually darker than the body and 
little spotted ; back, dorsal fin, and tail usually profusely covered with round black 
spots; these are sometimes very few, but very rarely altogether wanting; tail witha 
peculiar metallic silvery pigment; male about the spawning season (October) blackish, 
more or less tinged or blotched with dull red ; head conic, rather pointed in the females 
and spring males; jaws not emarginate either in front or on sides; maxillary rather 
slender, the small eye rather behind its middle; teeth small, longer on sides of lower 
jaw than in front; vomerine teeth very few and weak, disappearing with age; in 
the males in late summer and fall the jaws become elongate and distorted, and the an- — 
terior teeth much enlarged, as in the related species; the body then becomes deeper, 
more compressed, and arched at the shoulders ; preopercle very convex ; opercle strongly 
convex; body comparatively robust, its depth greatest near its middle ; ventrals in- 
serted behind middle of dorsal, ventral appendage half the length of the fin; caudal, as 
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