58 REPORT OF STATE BOARD OF FISH COMMISSIONERS. 



To this must also be added that the excellent figures accompanying 

 many of the reports, and which pretend to give the differences, are based 

 on sjsecimens which differed widely in size, and are therefore mislead- 

 ing. This last fact has undoubtedly much to do with the confusion 

 existing in regard to the Steel-head trout and Brook trout. 



The discussions whether a given fish may be a trout or Salmon trout, 

 while edifying to the man talking or writing, does not help us in the 

 least to clear this matter. 



In this connection it may be worth our while to examine the remarks 

 of Dr. Cliinther on the variability of the species of the genus Salmo, 

 remarks which Dr. Jordan had occasion to quote when studying these 

 same fishes: 



There is no other ijroup of fishes which offers so many difficulties to the ichthyologist, 

 with regard to the distinction of species, as well as to certain points in their life history, 

 as this genus. 



The almost infinite variations of these fishes are dependent on age, sex, and sexual 

 development, food, and the properties of the water. * * * The co/oraiion is, first of all, 

 subject to variation, and consequentlj' this character but rarely assists in distinguishing 

 a species, there being not one which would show in all stages of development tiie same 

 kind of coloration. The young of all the species of this genus are barred, and this is so 

 constantly the case that it maj' be used as a generic, or even as a family character, not 

 being peculiar to Salmo alone, but also to Thyinallus, and probably to Coregnnus. The 

 number of Ijars is not quite constant, but the migratory trout have two (and even three) 

 more than the river trout. When the salmons have passed the " parr" state, the color- 

 ation becomes much diversified. The males, especially during and immediately after 

 the spawning time, are more intensely colored and variegated than the females, speci- 

 mens which have not attained to maturity retaining a brighter silvery color, and being 

 more similar to the female fish. Food appears to have less influence on the coloration 

 of the outer parts than on that of the flesh; thus, the more variegated specimens are fre- 

 quently out of condition, whilst well fed individuals, with pinkish flesh, are of a more 

 uniform, though bright coloration. Chemistry has not supplied us yet with an analysis 

 of the substance which gives the pink color to'the flesh of many salmonoids ; but there is 

 little doubt that it is identical with, and produced by, the red pigments of many salt and 

 fresh-water crustaceans which form a favorite food for these fishes. The water has a 

 marked influence on the colors. Trout with intense ocellated spots are generally found 

 in clear, ra]iid rivers, and in small, open, alpine pools; in the 'iaroe lakes, with pebbly 

 bottom, the fish are bright-silvery, and the ocellated spots are mixed with, or replaced by, 

 X-shaped black spots ; m pools oj- parts of lakes, with muddy or peaty bottom, the trout are 

 of a darker color generallv. and when inclosed in caves or holes they may assume an 

 almost uniform blackish coloration. The brackish, or salt water, has the ett'ect of giving 

 them a bright-silvery coat, without or with comparatively few spots, none of which are 

 ocellated. * * * 



With regard to size the various species do not present an equal amount of variation. 



Size appears to depend on the abundance of food, and the extent of water. Thus, the 



salmon and the difterent kinds of Great Lake trout do not appear to vary considerably in 



size, because they find the same 'conditions in all the localities inhabited by them. 



* ** * ** *********** 



The proportions of the various parts of the body to one another vary exceedingly in one and 

 the same species. * * * The -fins vary to a certain degree. * * * 



Finallv, to complete our enumeration of these variable characters, we must mention 

 that in old males, during and after the spawning season, the skin on the back becomes 

 thickened and spongy so that the scales are quite invisible, being imbedded in the skin. 



Coregonus williamsoni Girard. Whitefish. 



This fish is abundant in Lake Tahoe. It spawns in October and 

 November in the tributaries of the lake. During the remainder of the 

 season the adult is probably found in deep Avater. In June, schools of 

 individuals, nine inches long, were seen on the eastern shores of the lake. 

 In the evening when swarms of gnats were l)lown into the lake these 

 Whitefish rose to them. A few were caught at the time with small hooks 

 baited with fly. It reaches a length of nearly fifteen inches, and weighs 

 about a pound. It ranks high as a food fish. Mr. Henshaw says of it: 



At Lake Tahoe it was found verv abundant in October, being met with at that 

 season in all the few streams that rise from the lake. * * * This month, and later, is 



