[VoL. 7 
28 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
TABLE XII 
(Series 4, II—Wheat [moist, low temperature]) 
SALT REQUIREMENTS AND H-ION CONCENTRATION IN RELATION TO GROWTH 
Total Total Greatest Pu 
No. UN gr. wt. dry wt. length 
accu (gms.) (gms.) (em.) Initial | After gr. 
1 AwO 3.72 .681 16.81 3.4 4.0 
2 Aw /5 10.87 1.373 22.90 4.6 6.0 
3 Aw /10 8.85 1.087 21.40 5.8 6.4 
4 Aw 1/ 4.42 736 16.75 3.35 4.0 
5 Aw 3/ 3.27 579 16.23 3.15 3.4-3.5 
6 AwNa 6.80 862 19.28 3.45 5.8 
7 AwM 11.24 1.323 24.20 5.4 6.6 
8 BwO 10.92 1.035 20.75 6.6 7.0 
9 Bw /5 8.40 912 19.27 7.4 7.6 
10 Bw /10 9.02 924 22.12 8.6 8.1 
11 Bw 1/ 7.97 908 20.69 6.4 T. 
12 Bw 5/ 9.17 910 20 .06 3.2 7.2 
13 Bw 10/ .90 209 8.80 2.8 3.6 
14 Bwk, /10 8.82 984 19.46 7.0 7.5 
15 BwCa 11.64 1.354 20.51 7.3 7.4 
16 CwO 6.75 870 18.54 4.2 Ta 
17 Cw /5 6.77 826 16.93 6.4 7.8 
18 Cw /10 5.60 681 12.85 7.6 8.6 
19 Cw 1/ 7.22 915 18.90 3.6 ta 
20 Cw 5/ 7.55 916 18.17 3.2 7.5 
21 CwNa 7.75 853 18.78 4.2 7.8 
temperature. On account of conditions prevailing at the time, 
sections I and 111 were actually maintained from 16 to 18 days. 
The plants in section 11 were permitted to run from 25 to 27 
days. This was an extreme test of the tolerance of these solu- 
tions, and no change of the nutrient medium was made in any 
culture throughout the entire period of growth. The water 
lost by transpiration was, however, replaced from day to day. 
A general survey of the blocks of cultures represented by 
solutions A, B, and C gives evidence that under conditions of 
rather moist air and high temperature (table x1) wheat grown 
without change of solution for 18 days exhibits less striking 
differences in the maximum growth quantities than may be seen 
in the earlier series of cultures. Nevertheless, the highest value, 
whether of total green weight or of dry weight, is found in culture 
