PLATE 73 



A. — Phaseolus vulgaris from Peru and Bolivia exposed to light from 9 a. m. to 4 

 p. m. Contained full-gro\\Ti seed pods when f)hotographed August 15, 1919. 



B. — Control series of Phaseolus left out of doors diuing the experiment. Showed no 

 indications of flowering when photographed August 15. 

 160115°— 20- — 5 



