REPORT OF STATE BOARD OE FISH COMMISSIONERS. 77 



on account of the extraordinary changes due to differences in surround- 

 ings, in sex and in age, and in conditions connected with the ]n-ocess of 

 reproduction. 



There are five species of sahuon {Oarorhytu-hus) in the; waters of the 

 North Pacific, all found on l)oth sides, hesides one other whicli is known 

 only from the waters of .Japan. These species may be called: (1) the 

 quinnat, or king salmon, (2) the l)lue-l)ack salmon, or rcdfisli, (;>) tlie 

 silver salmon, (4) the dog salmon, (5) tlie ]unnpl)ack salmon, and ((>) 

 the masu; or (1) Onrnrhyiichus tsckawytscha, (2) Oncorhyiirliu>i nerka, 

 (3) OncnrhynrJnis milJdschitch. (4) Oncorhynchus keta, (5) Onrorhyrirhus 

 gorbuscha, (6) Ortcorhyurlm>< nxisov. All these species save the last are 

 now known to occur in the waters of Kamchatka, as well as in those 

 of Alaska and Oregon. These species, in all their varied conditions, 

 may usually be distinguished by the characters given below. Other 

 differences of form, color, and appearance are absolutely valueless for 

 distinction, unless specimens of the same age, sex, and condition are 

 compared. 



The quinnat salmon {Onrorliyiirhas UchawytHclui)* , called quinnat, 

 tyee, chinook, or king salmon, has an average weight of 22 pounds, but 

 individuals weighing 70 to 100 pounds are occasionally taken. It has 

 about 16 anal rays, 15 to 19 In-anchiostegals, 23 (9+14) gill-rakers on the 

 anterior gill-arch, and 140 to 185 pyloric coeca. The scales are com- 

 paratively large, there being from 130 to 155 in a longitudinal series. 

 In the spring the body is silvery, the back, dorsal fin, and caudal fin 

 having more or less of round black spots, and the sides of the head 

 having a peculiar tin-colored metallic luster. In the fall the color is 

 often black or dirty red, and the species can then be distinguished 

 from the dog salmon by its larger size and by its technical cliaracters. 

 The flesh is rich and salmon-red, becoming suddenly pale as the 

 spawning season draws near. 



The blue-back salmon {Oncorhynchus nerka) \, also called red salmon, 

 sukkegh, or sockeye, usually weighs from 5 to <S pounds. It has about 

 14 developed anal rays, 14 branchiostegals, and 75 to 95 pyloric ca:>ca. 

 The gill-rakers are more numerous than in any other salmon, the 

 number being usually about 89 (16-f23). The scales are larger, there 

 being 130 to 140 in the lateral line. In the spring the form is 

 plumply rounded, and the color is a clear bright blue above, silvery 

 below, and everywhere innuaculate. Young fishes often sliow a few 

 round black spots, which disappear when they enter the sea. Fall 



*For valual)le accounts of tlie habits of this species the reader is referred to papers 

 by the late Cloudsley Rutter, ichthyologist of the Albatross, in tlie publications of the 

 United States Fish Commission, the " Popular Science Monthly," and the "Overland 

 Monthly." 



tPor valuable records of the natural history of this species the reader is referred to 

 various papers by Dr. Barton Warren Evermann in the bulletins of the United States 

 Fish Commission and elsewhere. 



