398 CHAP. XXXV. TORSION UNDER DIFFUSE STIMULATION 



may therefore be expected to be enhanced under the action 

 of feeble stimulation. 



Experiment 215. — A specimen of Thunbergia was in a 

 slightly subtonic condition, as evidenced by its slow rate 

 of torsion, which was 3 mm. per minute. The effect of 

 minimal stimulation for 4 minutes is given in the following 

 table : 



Table XLVII. — Effect of Minimal Electric Stimulus in 

 Enhancing the Rate of Torsion. 



The results show that feeble stimulation enhanced the 

 rate from 3 to the maximum positive of 43 in the course 

 of 6 minutes, after which there was the commencement 

 of recovery. The improvement of the tonic condition is 

 shown by the permanent enhancement of the rate from 

 the original 3 to 5. 



Other examples are given in the following table, in 

 which the maximum enhancement and permanent after- 

 effect are given in different columns. 



Table XLVIII. — Effect of Minimal Stimulation in Enhancing 

 THE Rate of Torsion in Different Plants. 



It has been stated that the effect of stimulation is 

 cumulative. Hence, with a stimulus of moderate intensity, 

 the effective stimulation is minimal at the onset and only 



