Juday—Studies on Some Mountain Lakes . 787 
Upper lake. 
Lower lake. 
1902. 
1903. 
1902. 
1903. 
July. 
August. 
July 
August. 
Aug. 
July 
August. 
Day of month. 
14 
20 
4 
14 
18 
26 
14 
7 
28 
21 
16 
8 
28 
Anurea cochlearis 
3.7 
1.0 
2.7 
1.6 
4.0 
2.0 
1.0 
1.6 
2.0 
38.1 
40.2 
12.4 
Anurea aculeata.. 
Notholca 
1.5 
18.0 
14.0 
0.4 
6.0 
7.0 
35.8 
28.0 
"i'.i 
52.4 
8.5 
. 
longispina . 
Triarthra 
26.2 
37.5 
10.7 
7.5 
5.3 
5.9 
19.7 
33.4 
31.2 
30.0 
37.0 
32.5 
30.4 
longiseta .. 
Polyarthra> sp. 
76.0 
66.9 
30.0 
38.2 
10.2 
5.5 
101.0 
8.5 
96.0 
8.0 
30.0 
3.8 
30.5 
9.0 
17.1 
24.0 
1.0 
2.7 
Asplanchna sp_ 
7.5 
8.1 
24.2 
31.7 
26.3 
33.8 
7.5 
9.6 
5.3 
9.6 
1.5 
7.5 
13.9 
Diaptomus judayi 
47.0 
25.1 
27.8 
15.0 
18.4 
22.5 
20.3 
107.6 
77.7 
57.6 
99.5 
68.9 
52.6 
Cyclops . 
Nauplii . 
Daphnia hyalina. 
71.9 
47.1 
35.3 
51.3 
52.6 
101.8 
40.1 
33.2 
47.1 
45.4 
88.4 
54.6 
55.0 
300.0 
237.5 
175.5 
145.5 
122.4 
104.0 
202.0 
201.0 
84.0 
84.5 
181.0 
142.3 
51.3 
young and adult 
Daphnia hyalina , 
157.9 
130.5 
58.2 
48.3 
25.0 
30.4 
27.8 
96.3 
64.2 
28.2 
151.0 
68.0 
64.6 
adult. 
37.0 
19.3 
12.4 
16.3 
5.3 
6.4 
9.0 
21.8 
30.3 
12.2 
58.4 
27.8 
28.0 
With respect to vertical distribution, Anurea cochlearis , 
Notholca longispina and Asplanchna were confined to the up¬ 
per ten meters. Anurea aculeata and Triarthra longiseta 
rarely occurred in the upper ten meters, being found almost 
entirely below this stratum. Polyarthra was rather evenly 
distributed throughout the entire depth of both lakes. 
There was no diurnal movement of Diaptomus, Cyclops 
and Nauplii, DapJinia hyalina showed a diurnal movement 
of half a meter in July and one meter in August. 
The phytoplankton made up a comparatively small portion 
of the total plankton and remained practically uniform in 
quantity during the two periods of these observations. The 
Crustacea made up by far the greater bulk of the total plank¬ 
ton. 
FOOD OF THE TROUT. 
Six species of trout are found in the lakes, and specimens 
of all except one species were' obtained for the purpose of 
studying their food. In all, 394 stomachs were obtained, of 
which 24 were empty, leaving 370 for study. An examina¬ 
tion of the contents of these was made in order to determine 
what the trout had been feeding on, as well as to determine the 
relative amounts of the various elements of the food. Only 
a very general classification of the stomach contents was at- 
