CHEMILUMINESCENXE OF ALGAE 



137 



to a higher level than it had maintained previously. It was not possi- 

 ble to make the luminescence rise indefinitely with successive bursts. 

 In Fig. 4 it will also be observed that the initial portion of the curve is 

 different from that of Fig. 1. The carbon dioxide effect was demon- 



is 



16 



iij 



Sl2 

 to 



1 10 



§8 



_i 

 1 6 



UJ 



^ 4 

 o 



2 







CHLORELLA 

 Ng -WATER 

 I I = "BURST" 0.2% CO2 



4 5 6 7 



IRRADIATION (MINUTES) 



10 



Fig. 4. Time course of delaj^ed luminescence during irradiation of Chlorella in 

 water. Nitrogen atmosphere. Effect of transient addition of carbon dioxide. 



18^- 



uj 16 — 

 o 



2 14 — 



UJ 



^ 12- 



UJ 



|lO- 



3 8- 

 6 — 



UJ 



I 



2 — 







CHLORELLA 

 No -ACID PHOSPHATE 



= CHANGE TO Oc 



L 



3 4 5 6 



IRRADIATION (MINUTES) 



7 8 



10 



Fig. 5. Time course of delayed luminescence during irradiation of Chlorella in 

 phosphate buffer. Nitrogen atmosphere. Effect of change to oxygen atmosphere. 



strated on the curve of the type in Fig. 1 also. The height of the initial 

 spike depended on the previous history of the sample. One-half hour 

 of anaerobiosis produced a high spike. These induction effects were 

 much reduced when the chemiluminescence was observed after only 

 a short dark period of anaerobiosis. Treatment with oxygen during 

 anaerobiosis in the dark, followed by careful flushing of the oxygen 



