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J. J. SKINNER 



1* to 100 parts per million. Duplicate sets of these cultures 

 were prepared, in one set plants were grown and in the second 

 set the bottles containing the solutions were allowed to stand. 

 At the end of three days the solutions were analyzed for nitrates, 

 nitrites and ammonia. This was done every three days, until 

 the plants had grown twelve days. The results of the analysis 

 after the plants had grown the first three days, and the final 

 green weight of the plants grown in each solution are given in 

 table 2. 



TABLE 2 



An examination of the tables shows that nitrites and ammonia 

 formed in the duplicate mannite solutions Nos. 1 and 2 and in 

 those solutions which contained mannite together with 1, 5 and 

 10 parts per million of salicylic aldehyde. In the solutions 

 which had no plants 25 p.p.m. and more of salicylic aldehyde 

 prevented any decomposition in the solution. In the solutions 

 with plants it required as much as 50 p.p.m. of salicylic aide- 



