CALIFORNIA PISH AND GAME 



107 



Scale counts from ten examples each from the followin;^' localities 



are given for comparison. 



Lateral series 



Lake Tahoe near Tallac 156 to 170 



Truckee River near Thisbe _- 157 to 165 



Pyramid Lake 153 to 162 



Salmo seleniris 168 to 176 



Above lateral line 

 31 to 35 

 30 to 34 

 29 to 35 

 29 to 31 



Fish 6 to 8| inches in length appear to be about three years old. 

 The growth is rapid during the season of active feeding. 



This trout is found only in the little streams of Fish Valley, a 

 remote region in Alpine County east of the Sierra Divide. Its native 

 habitat is restricted by Llewellyn Falls which form an impassable 

 barrier between the waters above and Silver King Creek below, which in 

 turn flows into Carson River. The 

 waters of the latter eventually dis- 

 appear in Carson Desert to the 

 eastward. Carson River was once 

 tributary to the Quaternary Lake 

 Lahontan which covered a consider- 

 able area in Nevada. Its fishes are 

 therefore related to or identical 

 with those of other rivers as the 

 Truckee, Walker and Humbod' 

 which were also tributaries to the 

 same ancient lake. This region or 

 basin, the streams of which have 

 not had any connection with the 

 ocean for untold ages, contains 

 native representatives of both the 

 rainbow and cutthroat fronts. The 

 rainbows are S. regalis of Lake 

 Tahoe, S. smaragdus of Pyramid 

 Lake, and S. aquilarum of Eagle 

 Lake. 8. henshawi, the more gen- 

 erally distributed trout is a cut- 

 throat, and its relationships are 

 aii]iarently with similar trouts of 

 the upper Columbia and Snake 

 Lake Basin. The 



FWJ. 20 



Sketch map showing Fish Valley 

 habitat of the Piute irout. 



native trout of the Colorado is 



rivers and Salt 

 related to these. 



Trout from below the falls are diflferent from those iinmediatel\- 

 above in that their bodies and dorsal and caudal fins are well covered 

 with large and very conspicuous roundish black spots. They are 

 also considerably deeper and more robust in appearance. The colors 

 are not nearly so bright. An enumeration of the spots on several 

 examples from the stream below the falls will be of interest. 



Spots on side of head 10 



On body above lateral line- 

 Body l)elow lateral line 



On tail above lateral line 



Tail below lateral line 



On dorsal fin 



Caudal fin 



