210 
Marsh—Limnetic Crustacea of Green Lake. 
DAPHNIA KAHLBERGIENSIS. 
D. kahlbergiensis did not occur in the collections from 1.96 to 7.96. 
No. 
of Coll. 
Total 
No. 
0-5 
5-10 
10-15 
15-20 
20-25 
25-30 
30-35 
35-40 
40- 
8.96.. 
40 
7.50 
60. 
20. 
10. 
2.50 
9.96.. 
225 
42.67 
17.78 
21.34 
17.77 
.44 
10.96.. 
129 
37.21 
18.60 
15.50 
24.81 
.78 
1.55 
1.55 
11.96.. 
71 
11.27 
56.34 
16.90 
7.04 
1.41 
4.22 
2.82 
12.96.. 
325 
39.38 
29.54 
24.62 
6.15 
.30 
13.96.. 
84 
14.29 
19.05 
47.62 
9.52 
9.52 
14.96.. 
32 
62.50 
37.50 
15.96.. 
5 
20. 
20. 
20. 
40. 
16.96.. 
108 
3.70 
81.48 
11.12 
.93 
2.77 
17.96.. 
68 
5.88 
35.30 
35.29 
22.06 
1.47 
18.96.. 
73 
21.92 
32.88 
35.62 
6.85 
1.37 
1.36 
19.96.. 
86 
37.21 
27.91 
9.30 
10.46 
13.96 
1.16 
20.96.. 
92 
60.87 
8.70 
6.52 
4.35 
13.04 
3.26 
2.17 
1.09 
21.96.. 
94 
34.04 
42.55 
8.51 
8.51 
1.07 
4.26 
1.06 
22.96.. 
78 
10.26 
30.77 
35.89 
12.82 
3.85 
2.57 
2.56 
1.28 
23.96.. 
223 
46.19 
17.94 
17.94 
10.76 
5.38 
.89 
.45 
.45 
24.96.. 
72 
13.88 
22.23 
33.34 
27.78 
2.77 
25.96.. 
61 
59.02 
26.23 
6.56 
6.55 
1.64 
26.96.. 
102 
in 
0-20 
met’rs 
27.96.. 
16 
18.75 
25. 
12.50 
6.25 
12.50 
25. 
During the fall of 1894 (see PI. XI) the collections of 
Daphnia kahlbergiensis were quite uniform in amount, reaching 
a maximum in the latter part of October. During the winter 
the number was very small, and they did not become numerous 
again until June. There is a fall maximum again in 1895 in 
the latter part of October, but, curiously, the total numbers 
collected during the fall of 1895 are much smaller than in 1894. 
During the winter and spring of 1896 Daphnia was entirely ab¬ 
sent from the collections. They appear again about the middle 
of May, and the largest collections of the year were made from 
June 29 to July 27. In August and September the collections 
were rather small, but the number became larger the latter part 
of October as in the preceding years. 
Apstein (’96, p. 170) states that the species of Daphnia reach 
their maximum in August, but that D. cederstroemi is somewhat 
later, so that it would appear that my results in regard to the 
seasonal distribution of Daphnia do not agree very closely with 
his. It is probable that the various species of Daphnia may 
differ considerable in their periods of maximum occurrence. 
