PLANT RESPONSE a 
(A) The first stimulus was given by a fall of the 
lever through /, the second through 2 h, and so on. 
The response-curves clearly show increasing eftect 
with increased stimulus (fig. 31). 

24° oP 74° 10? 123° 
Fig. 32.—iNcREASED RESPONSE WITH INCREASING VIBRATIONAL STIMULI 
(CAULIFLOWER-STALK) 
Stimuli applied at intervals of three minutes. Vertical line='1 volt. 
(B) 1. The vibrational stimulus was increased from 
25 to 5 to 7:5° to 10° to 12°5° in amplitude. It will 
be observed how the intensity of response tends to 
oO. 
approach a limit (fig. 32). 
TABLE SHOWING THE INCREASED E.M. VARIATION 
PRODUCED BY INCREASING STIMULUS 
Angle of Vibration E.M.F. 
2°5° 044 volt 
5° O7D) es 
To (020. 
102 JOOR 
12:5° 106 ,, 

