SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



• CONTINUOUS le.z 



• 60 S£C. 6.3 



■ /S S£C. 7.S 



■ s sec. ee 



■ 2 sec. 9.9 



10 sec. /3.0 



Fig. 10. — Effect of intermittent illumination for equal light and dark periods 

 of the indicated length on the carbon dioxide assimilation of wheat plants. 



