[Vox. 7 
34 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
TABLE XVIII 
(Series 4, II—Peas [moist, low temperature]) 
SALT REQUIREMENTS AND H-ION CONCENTRATION IN RELATION TO GROWTH 
Total | Gr. wt.| Total | Greatest Pa 
No. o gr. wt. | of roots | dry wt. | length 
mee’ | (gme) | (gms) | (gms) | (em.) | Initial | After gr. 
il 17.72| 6.55 | 1.772| 19.07 | 3.4 | 5.5-5.6 
2 | Ap/5 25.71| 12.17 | 2.200| 18.06 | 4.6 |6.0 
3 | Ap/10 24.26 | 9.72 | 2.299 | 20.00 | 5.8 | 5.9-6.0 
4 | Ap1/ 21.086 | 9.00 | 1.980 | 17.77 | 3.35 | 5.9 
5 | Ap3/ 22.52 | 9.44 | 2.183| 19.18 | 3.15 | 5.6 
6 | ApNa 20.69 | 8.52 889 | 17.61 | 3.45 | 5.7 
7 | ApM 25.65 | 11.20 | 2.310| 19.87 | 5.4 
8 | BpO 13.87 s% | 1 15.82 | 6.6 | 6.1-6.2 
9 | Bp/5 1465551 L| IH | 74 |71 
10 | Bp /10 18.57 | 7.54 | 1.704| 15.63 | 8.6 |7.6 
11 | Bp1/ 16.93 | 6.61 | 1.590 | 17.38 | 6.4 |6.0 
12 | Bp5/ a T | 125] 53951323 |60 
13 | Bp10/ 9.55 | 3.88 Bl 143098 | 258 155 
14 | BpK,/10 | 18.11| 8.90 | 1.455| 16.26 | 7.0 |6.2 
15 | BpCa 90.47 1 8.38 | 1.96612 31938 | 7.3 | 74 
16 | CpO 16.44 | 6.44 | 1.650| 13.85 | 4.2 | 7.2 
17 | Cp/5 135.845. 840 |] 1.78 | 10 1046 173 
18 | Cp /20 539] cu La se +70 i171 
19 | Cp1/ 16.36 | 6.95 | 1.599 | 13.61 | 3.6 |7.2 
20 | Cp5/ HDi 7.06 717001 195239 | 82 [84 
21 | CpNa Hals Tif 1738 | 43 170 
BpCa, as also by two cultures in the C block, namely CpO and 
Cp 1/. ; 
Wider differences are found in the case of peas grown at lower 
temperature in more humid air, but the maximum growth occurs 
in the A block, especially with the addition of a small amount of 
alkali (Ap /5) and in the ApM culture, containing both mono- 
basic and dibasic phosphates. No culture in the B block 
approaches the values referred to, and the same is true of the C 
cultures. Grown 16 days under dry conditions at a high tem- 
perature the yield of the various cultures is much reduced, and 
the relative values of the culture media do not remain the same 
as before. In this instance the B block exhibits the highest 
yields, especially cultures BpCa and BpK;/10. The next higher 
yield is found in Ap /10. In the A block the effect of high 
