466 
AMERICAN JOURNAL OF BOTANY 
[Vol. 9, 
Dry weights were obtained after the cultures had grown for sixteen days. 
The hydrogen-ion concentration of each culture solution was determined 
at the time the experiment was concluded. The results obtained are given 
in table 4. 
Table 4 
KH2PO4, Ca(N03)2, MgS04, KNO3, Ca(H2P04)2, MgS04 
II 
12 
13 
14 
15 
16 
21 
22 
23 
24 
25 
31 
32 
33 
34 
41 
42 
43 
51 
52 
61 
Richards . . 
Pfeffer .... 
Ciirrie . . . . 
Meyer .... 
Czapek 
Fusarium 
Dry 
Wt.* 
.2159 
•2163 
.2221 
.1876 
•1765 
.1895 
.2029 
•1755 
.2246 
.2601 
•2548 
•1835 
.2761 
.2^12 
•2334 
.1962 
.2317 
.4988 
.2236 
.2061 
•1399 
.1995 
pH 
5 
6.3 
6.4 
3.6 
5-4 
6.4 
3-9 
6.2 
6.4 
5-4 
4.6 
5-9 
6 
6 
4.8 
5-9 
5.6 
5-0 
5-8 
5.6 
5-2 
4.8 
I 
Fusarium 
Macrosporium 
Phoma 
n 
oxyspomm 
sarcinaeforme 
apiicola 
Rank 
Dry 
pH 
Rank 
Dry 
Wt.* 
pH 
Rank 
Dry 
pH 
Rank 
Wt.* 
Wt.* 
•I514 
3-6 
15 
•431 1 
6 
17 
-3448 
6-3 
7 
10 
.1422 
3-6 
17 
.3862 
5-7 
20 
.1627 
5-8 
12 
9 
.1369 
3.8 
18 
.4565 
5-4 
16 
-I514 
4-8 
14 
17 
.1216 
4.0 
19 
.4085 
6.2 
18 
•1567 
3-8 
13 
19 
.1160 
4.0 
20 
■3414 
5-0 
21 
.1019 
3-5 
19 
16 
.0985 
4.6 
21 
.3902 
5-0 
19 
.0269 
3-4 
21 
13 
•2133 
5-4 
21 
.6888 
7.0 
1 1 
-5301 
6-5 
3 
20 
.2326 
5-8 
9 
.8002 
6.0 
8 
.1265 
4-4 
16 
7 
.2089 
5-0 
12 
.6708 
5-2 
13 
.1764 
3-8 
2 
.1898 
5 
14 
.4904 
4.8 
15 
.0815 
3-8 
20 
3 
•1457 
5 
15 
•6352 
5 
14 
.1268 
3-6 
15 
18 
.2137 
6.4 
10 
.7685 
7-4 
9 
.4412 
6-5 
6 
I 
.2509 
6.2 
7 
.8195 
6.8 
6 
-6531 
6.2 
I 
4 
.2463 
5-4 
8 
1-0415 
5-4 
3 
.3128 
4.6 
8 
5 
•1939 
5 
13 
.900 
5-0 
5 
.1141 
18 
15 
.2718 
6.4 
5 
.6849 
7-2 
12 
.5864 
6.5 
2 
6 
.2588 
6.0 
6 
1.0149 
7-0 
4 
.5081 
6.8 
4 
14 
.2752 
5-4 
3 
1.2294 
6.2 
I 
.1161 
4.6 
17 
8 
.2727 
6.5 
4 
•7403 
7-2 
10 
.4805 
6.2 
5 
12 
•3183 
6.7 
I 
1-0735 
7.2 
2 
•3031 
6.2 
9 
21 
.2885 
6.8 
2 
.8054 
•4515 
•0973 
.0144 
.4187 
•1053 
8.4 
6.8 
4-6 
3-2 
5.2 
7-4 
7 
-2531 
-0952 
.0497 
.1473 
.3126 
6.2 
5-6 
3-8 
3-8 
6.8 
10 
* Average of three cultures. 
Figures 1,2,3, and 4 represent the arrangement of the triangular system. 
The area within the dotted line in each case represents the seven cultures 
making the best growth. 
The results of this experiment show clearly that a proper balance of 
the inorganic constituents in the solution is very essential, and that this 
balance can be readily obtained by the use of the triangular system. Using 
approximately the same concentration as Richards' solution and a constant 
source of carbon, the growth obtained in the balanced solutions was much 
superior for every organism used in the experiment. 
Summary and Conclusions 
I. Various synthetic solutions have been evolved to meet the needs of 
specific organisms. Fungi vary so much in their mineral and food re- 
