Growth of various Water Plants in Culture Solution , 355 
Table I. 
Series. 
I. Detmer’s solution 
II. Detmer’s solution + 
crude nucleic acid 
derivatives 
III. Detmer’s solution + 
autoclaved Azoto- 
bacter 
IV. Detmer’s solution + 
bacterized peat 
Dish No. 
ist week. 
2nd week. 
3rd week. 
1 
18 
2 5 
30 
2 
18 
22 
28 
3 
18 
23 
26 
4 
18 
23 
28 
5 
18 
24 
30 

• 

Mean 
18 
23.4 
28.4 
6 
26 
57 
179 
7 
24 
5 1 
163 
8 
26 
58 
189 
9 
2 3 
49 
156 
10 
24 
57 
184 
Mean 
24.6 
54-4 
174.2 
1 1 
20 
33 
61 
12 
19 
27 
5i 
13 
19 
28 
54 
14 
20 
32 
59 
15 
20 
29 
49 
— 
— 

Mean 
19.6 
29.8 
54.8 
16 
2 4 
65 
250 
17 
2 3 
7i 
272 
18 
22 
67 
258 
T 9 
22 
63 
246 
20 
2 5 
7 1 
250 
Mean 
23.2 
67-4 
255.2 
At the end of three weeks the numbers and also the appearance of the 
individual plants were so striking as to render the continuation of the whole 
series unnecessary, so on account of pressure of other work the experiment 
as a whole was brought to a close, although the dishes of Series I and IV 
were halved, one half of each dish being used for an estimation of the dry 
weight of the plants, and the other half of these two series being continued 
for a further period of three weeks. At the end of this time the average 
number of plants in Series I, resulting from the original 10, was 72, and that 
in Series IV 4,704. * 
At the time when the main part of the experiment ceased, three weeks 
after its commencement, the plants in Series I were extremely small and 
yellow and unhealthy in appearance. The plants, though not full-grown at 
the beginning of the experiment, had never increased in size, but had budded 
slowly, the new plants formed being successively smaller than the originals 
— so much so that it was quite easy at the end to pick out the original ten 
which were placed in the dishes, on account of their larger size. The 
plants in Series II, III, and IV at the end of the three weeks were all large. 
