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BROOKLYN BOTANIC GARDEN MEMOIRS 





Fig. I. Showing growth of sunflowers surrounded by wire netting. Note 

 difference in size of plants which have penetrated through the wire- mesh enclosure, 

 a feature of common occurrence. 



Methods 



In the study of the effects of contact of various materials with 

 plants we employed several methods and the experiments were carried 

 on under different conditions. With the exception of some of the 

 earlier experiments which were made out-of-doors, most of them were 



