1169 
TABLE 1. 
Strength of stimulus 900 mgs. Temperature 20° C. Reaction time 65 minutes. 
Fore-period Number of | Amount of curvatures 
in nitrogen | seedlings | in mm. 
5 hours a | scree C0 
1 EE AOT OG 
| 5 [1 Ye Ue Wp O 
| * \Ye Y% 0 0 
6 hours 8 | all without curvature 
BE 
5 id. 
2. Phototropic experiments. 
In these experiments also a preliminary stay of three hours was 
without the slightest effect on the curvatures, even six hours in 
nitrogen were not quite sufficient to prevent the reaction entirely, 
but an eight hotrs stay in nitrogen before stimulation was enough. 
TABLE 2. 
Strength of stimulus 40 M.C.S. Temperature 20° C. Reaction time 75 minutes. 
Fore-period Number of | Amount of curvature 
in nitrogen | seedlings in mm. 
6 hours 5 1, 1 Wy 1e 1 
8 I, We Ha U O 00 0 
7 EE A SD TT 
4 la Va Va Up 
6 kton ay yee ler ae f 
8 hours 6 all without curvature 
6 id. 
8 id, 
It is evident therefore, that the seedlings must be deprived of 
oxygen for a long time in order to lose their irritability altogether. 
