SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOLUME 97. NUMBER 2 



PLANT GROWTH IN RELATION TO 

 WAVE-LENGTH BALANCE 



(With Four Plates) 



BY 



EARL S. JOHNSTON 



Assistant Director, Division of Radiation and Organisms 

 Smithsonian Institution 



(Publication 3446) 



CITY OF WASHINGTON 



PUBLISHED BY THE SMITHSONIAN INSTITUTION 



JANUARY 12, 1938 



