92 SALMON AND TKOUT IN ALASKA. 



The average number of rows of scales varies from 43 to nearly 46, 

 with extremes 38 and 52. It was noted that the slender type form 

 usually showed a slightly smaller number of rows. 



In conclusion, it may be stated that the various counts, while not 

 amounting to demonstration, point to similarity in fishes from a given 

 basin rather than to a heterogeneous mixture of schools. In general 

 the environment at any one locality is very like that at any other; 

 hence if the output of each stream were entirely segregated there 

 would scarcely arise great differences of character among the different 

 lots. The range of variation is, in fact, so small that it appears to 

 fall within the possible effect of the personal factor if the counts were 

 made by different individuals; or of changing schools in any given 

 stream if made by the same individual in sequence. With measure- 

 ments, however, there is a difference. A sufficient number of fish 

 for the purpose can be measured in a few days spent at any one locality, 

 and the time element may be controlled by frequent change of place 

 and renewed examinations at each. The remarkable difference 

 found between the fish of such adjacent localities as Dolomi and the 

 Moira Sound streams clearly proves the value of such data.'' 



STREAMS NOT UTILIZED BY SOCKEYES. 



It is unfortunate in the study of Alaska salmon that almost no 

 streams not known to be frequented by sockeyes have been examined. 

 The only exception of importance is the Anan of Bradfield Canal, 

 which was visited on August 31, 1905. This stream is noted as the 

 earliest and most productive humpback stream in Southeast Alaska. 

 It is slightly less than the Naha in volume and about 3 miles in 

 length below the first lake. Nowhere in the course are any impedi- 

 ments to salmon at ordinary stages of water. The lake has about 160 

 feet of elevation, and on the above date had a surface temperature of 

 59.5°, about 1 degree higher than the stream. A tributary of the 

 stream was 54°. At that time humpback and king salmon in small 

 numbers were seen, and there were a few scattering red fish which 

 were thought to be sockeyes. Two humpbacks were seen to jump 

 in the lake. There is no apparent reason why sockeyes should not 

 ascend this stream in numbers equal to the runs in such streams as 

 those of Moira Sound. An examination of the lake might reveal some 

 obstacle to their natural propagation. There was notliing at that 

 season apparent in the surface densities or temperatures to deflect a 

 run entering Clarence Strait. From this strait through Ernest Sound 

 and into Bradfield Canal the temperatures were in general increasing, 

 54° to 58°, and densities decreasing, 1.020 to about 1.010. In Behm 



a For a similar study of the winter flatfish {Pleuronectes americanus) , see Hermon 

 C. Bumpus, On the identification of fish artificially hatched. American Naturalist, 

 vol. xxxii, June, 1898, p. 407-412. 



