46. SALMOXID^ ONCORHYNCHUS. 
307 
rich in spring, becoming paler in tbe fall as tbe spawning season 
approaches. Head 4 ; depth 4. B. 15-lG to 18-19, the number on the 
two sides always unlike. D. 11 ; A. IG. Gill-rakers usually 9-4-14 
{i. e., 9 above the angle and 14 below). Pyloric cceca 140-185. Scales 
usually 27-14G-29, the number in a longitudinal series varying from 
140-155, and in California specimens occasionally as low as 135. Verte- 
brte GG. L. 3G inches. Usual weight in the Columbia Eiver 22 pounds, 
elsewhere lG-18 pounds, but individuals of 70-100 iiouuds have been 
taken. Yentura Eiver to Alaska and Northern China, ascending all 
large streams; especially abundant in tbe Columbia and Sacramento 
Eivers, where it is the i)rincipal salmon. Upwards of 30,000,000 i^ounds 
are now taken yearly in the Columbia Eiver. It ascends the large 
streams in spring and summer, moving up, without feeding, until the 
spawning season, by which time many of those which started first may 
have travelled more than a thousand miles. After spawning, most or 
all of those which have reached the upper waters perish from ex- 
haustion. It is by far the most valuable of our salmon. It has lately 
been introduced into many eastern streams. 
{Salmo ishaivytscha* Walbaiim, Artedi Pise. 1792, 71: Salmo orientalis Pallas, Zoogr. 
Ross. Asiat. iii, 367, 1811-’31: Salmo quinnat Rick. Fauna Bor.-Amer. iii, 219, and of 
•writers generally: Oncorlnjnchus quinnat Gunther, vi, 158: Oncorhynchus orientalis 
Giintber, vi, 159: Oncorhynchus quinnat Jordan, Proc. U. S. Nat. Mus. i, 69: Fario 
argyreus Girard, Acad. Nat. Sci. jjjhila. 1856, 218: Salmo quinnat, confluenOis, and 
argyreus Suckley, Monogr. Salmo, 105, 109, 110: Salmo tschawytscha Bloch & Schneider, 
1801, 407.) 
\ 
aaa. Scales comparatively large, about 130 (125-135) in a longitudinal series; pyloric 
cceca 50-80. 
503. O. fisisaitcSl ("Walb.) Jor. & Gilb. — Silver Salmon; Kisutch; Skowitz; Roopid 
Salmon; Coho Salmon ; Bielaya Eyha, 
Bluish green; sides silvery, with dark punctulations; no spots except 
a few rather obscure on top of head, back, dorsal fin, adipose fin, and 
the rudimentary uiiper rays of the caudal; rest of the caudal fin un- 
spotted; pectorals dusky tinged; anal with dusky edging; sides of head 
without the dark coloration seen in the Quinnat; males mostly red in 
fall, and with the usual changes of form. Body rather elongate, com- 
pressed. Head short, exactly conical, terminating in a bluntly pointed 
snout, which is longer and broader than the lower jaw. Head shorter 
than in a young Quinnat of the same size. Interorbital space broad 
and strongly convex. Opercle and preopercle strongly convex behind ; 
the preopercle very broad, with the lower limb little developed. Cheeks 
* A barbarous spelling of the -word “chouicha” which we have thought prosier to 
simplify. 
