SALMON INVESTIGATIONS IN IDAHO IN 1895. 
159 
Iiartieularly on August 28. On August 21, I Avas astonished to see large numbers of 
squawhsh in Itedlish Lake feeding upon tliese buttertiies wliieli were dropping into 
the water. It was in the evening, when the cooling of the air benumbed the butter- 
tlies as they were passing over the lake. The squawtisb would sti ike at the buttertly 
the moment it fell upon the water, and in a manner much resembling that of the trout. 
A number of stomachs of trout and squawtish which we examined showed that for 
some days this butterfly constituted an important part of their food su])ply. 
Inlet . — Alturas Lake has but one inlet of aiiiy importance. This entei'S the lake 
near the nuddle of the shore at the upper end. It has its rise in the mountains south- 
west of the lake about 5 miles, in three principal forks, the middle one of Avhieh comes 
down the steep, rugged canyon from the summit over which passes the trail from 
Sawtooth to Atlanta. These three forks are all small, and fish of any size are not able 
to ascend far above their union. The upper portion of the canyon through which this 
creek flows is narrow, rocky in some places, but usually with a good growth of trees 
and bushes. Near its head the white-barked pine (Piuns aUncaHlis) is the most abun- 
dant, while lower down are the Douglas fir [Psemlotsnga douglasn), Engelmann’s spruce 
{Picea engelmanni)^ white spruce (Picea alba), and Murray pine {Pimts aiurrayana). 
Below the union of the three forks the canyon widens out and in the last 2 miles 
of its course it is perha[)S a mile in aAm'age width. The Murray pine grows thickly 
along the stream, but away from it on the left or west side this tree grows in small 
clumps or groves with level meadows intersi)ersed. At some places along the inlet the 
ground is marshy, and there is usually a thick undergrowth of Avillows and other bushes. 
In its lower portion this creek is a stream of considerable size, averaging about 25 or 
30 feet in width and varying greatly in depth. 
On September 17 the measurements of the inlet at its mouth were as follows: 
Width, 40 feet; average depth, 10.4 inches; average current, ly feet per second. This 
would indicate a discharge of about 18,000 gallons per minute. The stream was 
measured on the same day at our camp, about half a mile above the mouth, and 
the following results obtained: Width, 14| feet; average depth, 10 inches; average 
current, 3|4- feet per second, thus indicating a volume of about 21,000 gallons 
per minute. The lack of agreement between the two results is probably due to an 
underestimate of the ividth and depth at the mouth. The left bank at the mouth 
overhangs considerably, and sufficient allowance was lu’obabl}'^ not made for the water 
running under it. During the early part of the summer the volume of water flowing- 
in this creek was considerably greater, perhaps as much as 28,000 gallons, Avhileatthe 
lowest stage of water the volume is probably not greater than 17,000 gallons. At the 
time of our measurements the flow was somewhat above low stage, on account of recent 
rains. 
The banks of the creek are low and composed of sandy soil, or in some iflaces of 
sand or gravel. The stream bed is of moderately coarse gravel on the riffles in the 
upper portion, and smaller gravel in similar iilaces in the lower portions. But through 
most of its course the bed is of very flue gravel and sand. Occasionally there is some 
mud bottom, but this is very rare. The bed is remarkably clean and free from debris 
or filth of any kind. 
The depth of the water in most places varies from a few inches to 2 feet or less, 
though there are numerous “holes” where the depth varies from 2 to 4 or 5 feet. A 
deep hole rarely extends entirely across the creek, but lies over toward one bank, the 
