REPORT OF STATE BOARD OF FISH COMMISSIONERS. 49 



conclusions have been independently reached by Dr. Tarleton H. Bean, 

 of the United States Fish Commission, who had several times visited 

 Alaska for the i)urpose of investigating its salmon fisheries, and whose 

 means of studying the dift'erent species has been as extensive as ours. 

 It is very gratifying to see that the results of these different sets of 

 observations agree in all essential respects, and also agree fully with the 

 observations made so long ago by Steller. 



All of these authorities recognize the existence of five species of 

 Oncorhynchus inhabiting both shores of the North Pacific. There is no 

 evidence of the existence of any more on either the American or the 

 Asiatic side. These species may be called: (1) The Quinnat, or King 

 salmon; (2) the Blue-back salmon, or Red-fish; (3) the Silver salmon; 

 (4) the Dog salmon, and (5) the Humpback salmon; or (1) Oncorhyn- 

 chus tschawytscha; (2) Oncorhynchus nerka; (3) Oncorhynchus kisutch; 

 (4) Oncorhynchus keta, and (5) Oncorhynchus gorbuscha. All these 

 species are now known to occur in the waters of Kamtschatka as well as 

 in those of Alaska and Oregon. These species, in all their varied con- 

 ditions, 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 King salmon, or true Quinnat, or Chinook salmon {Oncorhynchus 

 tschawytscha), 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 branchiostegals, 23 (9+14) gill-rakers on the anterior gill 

 arch, and 140 to 185 pyloric coeca. The scales are comparatively large, 

 there being from 130 to 155 in a longitudinal series. In the spring the 

 body is silvery, tlie 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 tlie color is often black or dirty red, 

 and the species can then only be distinguished from the Dog salmon by 

 its technical characters. 



The Blue-back salmon {Oncorhynchus nerka) usually weighs from 5 to 

 8 pounds. It has about 14 developed anal rays, 14 branchiostegals, and 

 75 to 95 pyloric coeca. The gill-rakers are more numerous than in any 

 other salmon, the number being usually about 39 (16-|-23). 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 immaculate. Young fishes often show a 

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

 specimens in the lakes are bright red in color, hook-nosed, and slab- 

 sided, and bear little resemblance to the spring run. Young spawning 

 male grilse are also peculiar in appearance, and were for a time consid- 

 ered as forming a distinct genus, under the name of ^^Hypsifario ken- 

 nerlyi.'^ This species appears to be sometimes land-locked in mountain 

 lakes, in which case it reaches but a small size. Such specimens, called 

 " Kokos " by the Indians, have been sent us from Lake Whatcom, Wash- 

 ington, by Mr. T. .J. Smith, of Whatcom. Similar specimens have been 

 sent in from other mountain lakes. 



The Silver salmon {Oncorhynchus kisutch) reaches a weight of 3 to 8 

 pounds. It has developed rays in the anal, 13 branchiostegals, 23 

 (10+13) gill-rakers, and 45 to 80 pyloric coeca. There are about 127 

 scales in the lateral line. In color it is silvery in spring, greenish 



^43 



