446 
Birge—The Crustacea of the Plankton. 
Table H.— D. retrocurva. Average, maximum , and minimum num 
bers. Percentile vertical distribution. 
Av. 
Max. 
Min. 
Per cent, in each 3 m. level. 
0-3. 
3-6. 
6-9. 
9-12, 
12-15 
15-18. 
1895. 
July 1-15.... 
9.7 
14.6 
0.0 
47.0 
25.5 
13.1 
14.4 
0.0 
0.0 
July 16-31... 
31.5 
59.7 
3.5 
50.0 
24.0 
24.8 
1.2 
0.0 
0.0 
Aug. 1-15... 
68.2 
154.8 
8.9 
37.1 
26.1 
16.8 
18.5 
1.3 
0.1 
Aug. 16-31.. 
50.1 
96.0 
20.5 
41.1 
21.3 
22.7 
13.7 
1.1 
0.1 
Sept. 1-15... 
23.8 
37.5 
11.5 
46.4 
23.5 
20.3 
6.4 
2.9 
0.5 
Sept. 16-30.. 
59.6 
74.4 
21.6 
33.8 
24.1 
15.7 
11.6 
7.8 
6.9 
Oct. 1-15_ 
72.5 
103.6 
50.9 
35.9 
15.2 
17.9 
7.5 
11.7 
11.7 
Oct. 16-31... 
70.9 
65.5 
33.7 
29.2 
10.0 
12.3 
10.6 
9.1 
28.7 
Nov. 1-15.... 
59.3 
79.5 
42.6 
24.2 
20.2 
12.6 
18.4 
14.2 
10.3 
Nov. 16-30... 
24.2 
37.5 
19.1 
30.7 
20.2 
14.9 
12.3 
10.0 
11.9 
Dec. 1-15.... 
5.0 
11.4 
1.9 
3.7 
0.0 
41.3 
17.5 
18.7 
18.7 
Dec. 16-31... 
0.7 
0.9 
0.0 
0.0 
0.0 
27.3 
36.4 
18.2 
18.2 
1896. 
July 16-31... 
2.5 
Irreg 
ular 
near 
surfa 
ce. 
Aug. 1-15... 
27.6 
59.0 
32.4 
8.0 
0.4 
0.2 
0.0 
Aug. 16-31.. 
57.1 
36.5 
23.2 
24.0 
14.0 
2.3 
0.0 
Sept. 1-15... 
157.7 
26.2 
17.3 
19.3 
19.4 
12.4 
5.3 
Sept. 16-30.. 
228.6 
26.5 
18.4 
15.4 
16.3 
12.0 
11.4 
Oct. 1-15.... 
199.3 
26.4 
20.0 
14.3 
10.8 
13.0 
15.5 
Oct. 16-31... 
92.7 
43.5 
18.8 
8.8 
10.8 
10.4 
7.6 
Nov. 1-15_ 
9.9 
29.0 
30.7 
0.0 
0.0 
13.5 
26.8 
