198 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
the question. The statistics of the catch of bluehack salmon in the Fraser River, as furnished by the 
Canadian Department of Marine and Fisheries, show a periodicity in the ruu in that river. Whether 
there is any connection between the runs in these two rivers, whether a large run in the one is at the 
expense of that in the other, is improbable, but Avell worth investigation. 
Another explanation suggests itself: It is possible that at some time, years ago, a catastrophe 
of some kind or other may have occurred iu the headwaters of the Columbia which resulted in the 
destruction of practically all the tish and spawn in the river at that time. Then, upon the supposition 
that this species reaches maturity in two years (which is wholly improbable), and that it spawns 
only once (which our observations proved), there would be few if any fish to come to the spawuing- 
grouuds the second year after the catastnqihe; and this break would be self-perpetuating, and thus 
would the light run on alternate years be accounted for. 
The principal, and I think fatal, weakness in the hypothesis is the supposition that this salmon 
spawns at 2 years of age. Our observatious at Alturas Lake indicate that the young remain near 
where they were hatched for about one year, and that at 1 year old they are only about 6 inches long. 
To go down to the sea, grow to a length of 2 feet or more and a weight of 5 to 7 pounds, and then 
return to the spawning-beds, would at the lowest possible calculation require at least two years more. 
Each of these hypotheses appears very improbable and unsatisfactory. The solution must wait 
for additional knowledge concerning the life-history of the species. 
16. Salmo mykiss Walbaum. Columbia Hiver Trout ; Cut-throat Trout ; Blaclc-spotted Trout. 
Black-spotted trout are abundant in all suitable waters in Idaho. Our collections of 1894 and 
1895 contain numerous specimens, representing the following localities : Snake River at Upper Salmon 
Falls; Mann Creek 10 miles from Weiser ; Little AVeiser River at Indian Valley ; Payette River and 
Big Payette Lake; Big Wood River near Galena; Beaver Creek, Alturas Lake, Alturas Creek, 
Meadow Creek, Warm Springs Creek, and Salmon River near Sawtooth, and Fish Lake near Redlisb 
Lake. A study of these specimens has not led to any satisfactory conclusion as to what varieties, if 
any, should be admitted. 
The specimens from Upper Salmon Falls and Manir Creek have the small scales and the red throat 
of subspecies clarkii, as defined by .Jordan & Evermann. The numerous examples from Payette 
River and Big Payette Lake are less spotted, and have little, if any, red upon the throat. Two speci- 
mens caught iu Big Payette Lake September 27, 1891, had the following colors: A male, 15 inches 
long — spots small, half circles, few below middle of side; rosy wash on side and opercles; scarcely 
any red on throat; belly silvery, back dark-greenish; scales about 145, gillrakers lO + lO, branchi- 
ostegals 11, anal 12; stomach enqity, except three pine seeds. A fem:ile, 14f inches long, had the 
sirots the s:uue as iu the male, the sides less rosy, and scarcely any red on throat; scales about 140, 
gillrakers 7 + 12, brauchiostegals 11, an:il 11; stomach filled with small crustaceans. 
Two other examples taken iu the same lake September 27 possessed essentially the same color 
markings, as do also the specimens sent in by Mr. Williams. These are certainly the variety gihbsii, 
and are locally known as the silver trout. They are abundant in Big Payette Lake. On the morning 
of September 27, while sailing from the foot to the head of this lake, trout could be seen jumping iu 
various places; one or more could be seen at any time, while usually 5 to 15 or 20 could be seen jump- 
ing out of the water and glittering in the morning sun. They are said to sx)awn at this lake iu .June^ 
running up the smaller streams for that xmrpose. 
Trout are very abundant iu the uj)perpart of Big Wood River, and the collections contain several 
specimens from the vicinity of Galena. A fine specimen, a female 14 inches long, taken with the fly 
by Mr. Barnum iu this stream September 24, had the following life colors: Back, dark steel color, 
thickly covered with small round black spots ; middle of side and cheek with a broad wash of rosy 
red; lower parts silvery; black spots very numerous on back and on dorsal and anal fins, less thick 
below lateral line; no red on throat. Other examples from the same stream were examined and found 
to agree with the one just described iu the abundance of spots, the rosy sides, and the almost entire 
absence of red on the throat. 
These AVood River trout seem, therefore, closest to variety f/ibbsii. 
Young trout were found to be abundant in the Redfish Lake.s, while iu the streams of the Upper 
Salmon Valley trout ranging from one-fourth of a pound up to 2 or 3 pounds were very plentiful. 
Among the streams that afforded particularly good trout fishing were Beaver, Smiley, Pole, and Alturas 
creeks and Salmon River. During our stay the best fishiug was in .Tuly, but in the smaller streams 
