DECAY OF THE DELAYED LIGHT IN Cfllorclla 



129 



general, no simple relation has been found between the intensity of 

 the delayed light and the time in the dark; for this reason, the results 

 will be presented only in graphical form. 



All measurements of the intensity of the delayed light were made 

 with an RCA #6217 Photomultiplier, at the temperature of dry ice, 



>« 



O 



— r- 

 4 



6 



TlME(min) 



Fig. 2. The reciprocal of the square root of the intensity of the delayed light as 

 a function of the time in the dark. Numbers on the curve indicate relative in- 

 tegrated light energy of the exciting flash. 



and with a vibrating reed electrometer. Since the decay covers a wide 

 range of time, three different methods of study were used. 



For the middle part of the decay curve the flowing method de- 

 scribed by Strehler and Arnold (1) was used, where the time in the dark 

 is the time that the Chlorella spends in flowing between the illuminated 

 vessel and the measuring vessel. Each cell spends most of the time 

 in the light, making periodic excursions through the pumping system. 



