[fraser] PACIFIC SALMON 169 



five species as far as it had been worked out and supplied a great 

 fund of statistical and commercial information. A new edition, 

 brought up to date in 1917, is invaluable for reference on almost 

 every matter in connection with the salmon industries. 



Greene, in several papers from 1911 to 1914, gives much infor- 

 mation on the anatomy and physiology of the chinook salmon, but pos- 

 sibly his most important single contribution, as far as life-history 

 work is concerned, was that showing that the chinook may stay near 

 the meeting place of the salt and fresh water for as much as 30 or 40 

 days, going backward and forward in the meantime. 



In 1907, Evermann and Goldsborough gave further information 

 as to salmon runs in Alaska, with which was coupled a good biblio- 

 graphy. In the same year Chamberlain published "Some Observa- 

 tions on Salmon and Trout in Alaska," a paper of much importance, 

 since in it he went into a detailed description of the five species of 

 salmon, traced migratory movements and took into account the size 

 and appearance of th-^se fish at various times in fresh and in salt water. 

 He concluded that there was a greater tendency for the young fish 

 to remain over in fresh water for a year or more in large streams than 

 in small. A large number of spring, sockeye and coho remain over 

 for at least a year, but humpbacks and dogs pass out to the sea shortly 

 after hatching. Sockeye do not show the same rate of growth in differ- 

 ent river systems nor the same amount of growth in different years. 



McMurrich, in 1909, gave an account of the life-history of the 

 five species, making the first mention of making use of otoliths in age 

 determination of these speciss. This was followed by another paper in 

 1912, in which the first attempt at age determination by means of the 

 scales in these salmon was attempted. In the next year Milne did 

 some work along this same line and found what he supposed to be a 

 spawning mark on the scale of a spring salmon. In the same year 

 Gilbert published a paper on age determination, in which, as he exa- 

 mined a great number of specimens, he went much more fully into 

 the different types. He demonstrated the difference in the nature of 

 the scale of a fish that migrated as fry (sea-run) and of that of one that 

 remained in fresh water for a year or more (stream-run). In his later 

 papers he has dealt with sockeye and in them has done much to show . 

 that each river system has its own characteristic fish, and hence, 

 that all Pacific salmon tend to return to the spawning grounds from 

 which they began to migrate. 



In 1915 and 1917, the writer showed that the record obtained by 

 age determination and growth calculation from the scales in the case 

 of the spring and coho was corroborated from direct observation of 



