1913.] PUBLIC DOCUMENT — No. 31. 37 



Tnvostigatioiis rclaliiii>' to light in grcenhons(^s ; practically 

 completed. 



Experiments with methods of treating tree cavities. 



Experiments with the effects of varying percentages of soil, 

 moisture and air on tlKTgermination of seeds. 



Experiments with the effects of ozone on seed germination 

 and varions plant activities. 



These investigations have been carried on in some cases for 

 some time, and several of them wonld properly come under the 

 heading, " Investigations of the effects of meteorological condi- 

 tions on the diseases and the development of plants in general," 

 which we are studying under the " Adams fund." 



