REPOKT OF STATE BOARD OF FISH COMMISSIONERS. 61 



have been able to examine about seventy-five Brook trouts from difier- 

 ent streams, and others have come into my hands from Mr. Belding. 

 Although the alcohol has obliterated most of the color markings, it can 

 still be seen that no two streams have trout with exactly the same 

 characters. To add to the confusion, the young of the salmon greatly 

 resemble the trouts, and the old trouts greatly resemble the salmon. 

 Young salmon have been brought to me as Brook trouts; and I bought 

 a splendid Brook trout, nineteen inches long, which the fish dealer de- 

 clared was a salmon, and willing to jDrove it by as large a bet as I would 

 name. 



I do not know where trouts have been planted, and where those so 

 planted were procured, but the native species are distributed as follows: 



1 . The Brook trout, or Rainbow trout ( Salmo gairdneri irideiis Gibbons) , 

 in all mountain streams west of the Sierra Nevada from Mount Shasta 

 to Lower California. 



2. The Steel-head {Salmo gairdneri Richardson), from the Sacramento 

 northward. 



3. The Northern trout {Salmo purpuratus Pallas), from Mount Shasta 

 northward. 



4. The Tahoe trout ( Salmo purpitratus henshawi Gill and Jordan ) , in the 

 Truckee Basin, including Lakes Tahoe, Donner, Pyramid, and possibly 

 Eagle. 



It is thus seen that three of the trouts inhabit contiguous territory, 

 while the other, the Steel-head, overlaps the territory of two of the species. 

 There are, however, so many forms which are intermediate between the 

 Brook trout proper and the Steel-head that the former may be looked 

 upon as simply a southern form of the latter, or, conversely, the latter a 

 northern form of the former. 



These species and varieties are extremely hard to distinguish unless 

 specimens of the same size are at hand. They may be determined by 

 the following technical characters arranged by Dr. Bean: 



a. No hyoid teeth. 

 i. Anal rays, 12 ; depth of body equals length of head in young ; tail of adult trun- 

 cate S. gairdneri; Steel-head. 



bb. Anal rays, 10; depth of body much exceeds length of head in young; tail of 



adult forked S. gairdneri irideus; Brook, or Rainbow trout. 



aa. Hyoid teeth. 



c. Head short ; scales, not more than 170; gill rakers, 8-12; cceca, 20 



S. purpuratus ; Northern trout. 



cc. Head long, conical ; scales, sometimes 184 ; gill rakers, 9-14 ; cosca, 50-60 



.S. purpuratus henshawi; Tahoe trout. 



Salmo gairdneri Richardson. Steel-head Salmon. 



This trout is not infrequently brought into the San Francisco mar- 

 ket during the close season. At other times it is not so abundant, and 

 in summer and fall it is rarely seen. It reaches a weight of twenty 

 pounds. The California Academy of Sciences possesses a large specimen , 

 the gift of Mr. Charles Ohm. It measures two feet five inches in length, 

 and is a spent male. 



There are several others smaller than this in the Academy's collection, 

 presented by the same gentleman. It is more slender than the Rainbow 

 trout or the Quinnat salmon, and does not ascend streams to any great 

 distance. 



Very little or nothing is known of the habits and life history of this 

 species, and any notes on its migration, etc., ought always to be kept. 



