88 CHAP. XI. PHENOMENON OF PHOTOSYNTHETIC INDUCTION 



was generally at the fourth bubble that the normal rate of 

 20 seconds was restored. 



In the second experiment of the series the constant 

 source of light was Pointolite. The effect of increasing 

 duration of previous darkness is given in the tabular state- 



Fig. 26. Successive Records showing Increasing Induction- 

 periods with Increasing Duration of Previous Darkness 



Note that not only is the period of the first bubble delayed, but 

 also the second bubble. The record c at the top shows 

 successive bubbles at 20 seconds' interval under continuous 

 light. 



ment on p. 89. The normal period under continuous 

 light was 25 seconds. 



I also reproduce automatic records, obtained in the first 

 experiment, of the effect of increasing periods of previous 



