348 Bottomley. — The Growth of Lenina Plants in 
Detmer’s solution, and those of Series II, numbered from 6 to 10, a similar 
quantity of the same solution together with the extract of i grm. of 
bacterized peat in every i,oooc.c. Series III and IV were precisely similar 
to Series I and II respectively, except that Knop’s solution was used instead 
of Detmer’s. Ten plants of Lemna major were put into each dish, and fairly 
young plants were chosen instead of quite full-grown ones, in order that 
a more uniform selection as to size might be made. The dry weight of 
three separate hundreds of similar plants was estimated, and found to be 
36-6, 36*0, and 34-8 mg. respectively, giving an average of 35-8 mg. per 100 
plants. The dishes were treated precisely as before* their solutions being 
changed twice weekly and the plants counted once weekly. They did not 
multiply nearly so rapidly as did the Lenina minor, and so there was no 
necessity to halve the contents of the dishes, though the experiment lasted 
for five weeks. The number of plants obtained 
course of the experiment are shown below. 
Table III. 
each 
week during the 
Series. 
Dish 
\st 
2nd 
3 rd 
4 th 
5 th 
No.. 
•week. 
week. 
week. 
week. 
week. 
I. Detmer’s Solution 
1 
27 
33 
44 
57 
62 
2 
27 
34 
44 
53 
57 
3 
18 
24 
28 
39 
43 
4 
24 
25 
34 
40 
45 
5 
22 
32 
39 
41 
4 1 

— 
- — 
— — - 
- ■ — . 
Mpan 
23.6 
29.6 
37-8 
46 ; o 
49.6 
II. Detmer’s Solution + 
6 
3 i 
50 
7 2 
i 1 5 
161 
Bacterized Peat 
7 
31 
45 
62 
102 
126 
8 
30 
48 
75 
1 18 
154 
9 
47 
7 ° 
1 10 
150 
io 
27 
43 
100 
129 
— 
- 
■ — - 
— 
— 

Mean 
29^6 
46-6 
67.8 
ib9 ; o 
144.0 
III. Knop’s Solutioii 
it 
18 
23 
25 
29 
3 1 
1 2 
25 
26 
28 
3 i 
3 i 
13 
22 
23 
28 
29 
29 
H 
l8 
21 
27 
29 
29 
15 
22 
24 
27 
28 
30 
- — — 
■ 
— 
— 
— 

Mean 
2IoO 
2 3-4 
2 7 °o 
29*2 
30.0 
IV. Knop’s Solution + 
16 
3 i 
45 
75 
162 
Bacterized Peat 
17 
29 
40 
53 
77 , 
112 
18 
29 
45 
70 
82 
130 
r 9 
28 
35 
49 
63 
96 
108 
20 
27 
44 
7 i 
! 5 r 
— 
— 
• 
— 
— 
Mean 
28-8 
41-8 
63.6 
83.2 
132-6 
At the conclusion of the experiment the dry weight of the contents of 
three of the dishes in each series was estimated, and from the figures 
obtained the weight of 100 plants was calculated. The results were as 
follows : 
