Salmonidas 



6 9 



characters given below. Other differences of form, color, and 

 appearance are absolutely valueless for distinction, unless speci- 

 mens of the same age, sex, and condition are compared. 



The quinnat salmon (Oncorhynchus tschawytschd) ,* 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 branchi- 

 ostegals, 23 (9 + 14) gill-rakers on the anterior gill-arch, and 

 140 to 185 pyloric cceca. The scales are comparatively 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 



FIG. 53. Quinnat Salmon (female), Oncorhynchus tschawytscha (Walbaum). 



Columbia River. 



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 characters. The flesh is rich and salmon-red, 

 becoming suddenly pale as the spawning season draws near. 



The blue-back salmon (Oncorhynchus nerkd},\ also called 

 red salmon, sukkegh, or sockeye, usually weighs from 5 to 8 

 pounds. It has about 14 developed anal rays, 14 branchioste- 



* For valuable accounts of the habits of this species the reader is referred 

 to papers by the late Cloudsley Rutter, ichthyologist of the Albatross, 

 in the publications of the United States Fish Commission, the Popular 

 Science Monthly, and the Overland Monthly. 



f For 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. 



