78 
BULLETIN OF THE BUREAU OF FISHERIES. 
Large numbers of blue-nosed trout ( Salmo virginalis ) and Williamson’s white- 
fish are taken from the lake. The trout are taken on set lines and in gill nets by 
the market fishermen. It is stated that they will not take a fly or trolling bait of 
any kind, so are of little interest to the sportsman. Chubs and suckers are the only 
fish caught in the lake by angling. Black bass have been planted in Mud Lake (a 
small shallow lake cut from the north end of Bear Lake), and a few have been 
caught. 
Only two forms of Crustacea were found in the lake, namely, Epischura neva- 
densis and Canthocamptus northumbricus. Epischura was found throughout the 
entire depth of the lake, but the maximum number was in and above the thermo- 
cline. In the 10-15 m. stratum the number ran as high as 5,980 individuals per 
cubic meter of water. This distribution is characteristic of Epischura, for it rarely 
inhabits the region below the thermocline. The fact that Canthocamptus was found 
only in the 50-55 m. stratum is a most peculiar distribution. Just why it should 
be found only near the bottom of the lake is hard to say. A more complete study 
of the situation might reveal some interesting facts regarding this strange distri- 
bution. 
Nauplii were found in every catch except in the 0-5 m. and the 42^-47^ m. 
strata. Three-fourths of them were found below the thermocline. and an especially 
large number was found in the 50-55 m. stratum. 
The only rotifer found in the lake was Polyarthra platyptera. It was found in 
rather limited numbers in the 5-15 m. stratum, that is, in or above the thermocline. 
As a whole the zooplankton was rather scarce in Bear Lake. 
Ceratium was found in the 5-10 m. stratum and numbered 15,690 per cubic 
meter of water. 
The algse were found just above the thermocline in the 5-10 m. stratum. 
Fragilaria was the only diatom, and the maximum number found was 7,850 per 
cubic meter of water. The blue-green alga Ccelosphaerium was found to number 
7,850 per cubic meter of water. Little vegetation existed along the shores, except 
at the north and northwest ends of the lake. 
CALVERT LAKE, WASH. 
This is a very small lake between two low hills. The upper and lower ends 
of the lake are shallow and marshy. Cladocera, Copepoda, nauplii, and Protozoa 
were most abundant in the 0-2 m. stratum. 
LAKE CHATCOLET, IDAHO. 
Lake Chatcolet presents an illustration of another type of lake in that at the 
bottom (11 m.) there was no dissolved oxygen. Both plants and animals were very 
abundant, and under the above-stated conditions it was to be expected that the 
Crustacea especially would be confined to the upper stratum of water where the 
free oxygen was more abundant. Somewhat more than 98 per cent of the copepod 
Diaptomus ashlandi occupied the 0-5 m. stratum. (See Table 12, p. 123.) This was 
found to be the case in the vertical distribution of Cyclops bicuspidatus and Daphnia 
hyalina. They were much more abundant in the upper water, although not as 
strikingly so as in the case of Diaptomus. Diaphanosoma leuchtenbergianum was 
