974 



THE LIGHT FACTOR. I. INTENSITY 



CHAP. 28 



250 



200 - 



I 150 



o 



100 



50 



3 X 10" 

 LIGHT INTENSITY, erg/cm^ sec. 



3 X 10* 



Fig. 28.8. Light curves of purple bacteria (Chromatium D) at different temperatures 

 (after Wassink, Katz and Dorrestein 1942). (5% CO2, concn. 1, corresponding to ca. 

 80% absorption of sodium light; cf. fig. 28.22.) 



200 



05 ml 03% KCN/ml 



J L 



i 1.45x10* 



INTENSITY, erg/cm sec 



Fig. 28.9A. Light curves of HCN-inhibited Chlorclla cells 

 showing that HCN is ineffective in weak light (after Wassink, 

 Vermeulen, Reman and Katz 1938). 



