1910.] 



rimLIC IHXUIMENT — No. 31. 



229 



A coiii])arisoii of the last two experiments sliows Low much 

 less sensitive cuciiml)ers are in cloudy weather. 



Experiment III. 



Cloud)/ Day Exposures with Older Plants, April 26, 29, 



May 8, 16. 

 Fumigation with .01 gram KCIST per cubic foot; sunlight 

 a })ortion of each day, hut not during treatment ; plants w^atered 

 the day before the treatment ; conclusions drawn after one week. 



Experiment IV. 



Cloudy Day Exposures with Stronger Fumigation, May 23, 27. 



Fumigation with .015 gram KCIST per cubic foot; plants 



of first tw^o sets sixteen days old, fumigated May 28 ; of the 



other sets twenty days old, fumigated May 27; amount of sun- 



