PAPERS ON AGRICULTURE 



99 



In no case does germination appear. In general we see 

 that the sudden bursting becomes less prevalent as the concen- 

 tration increases. 



For example, in cane sugar, in the weak solution all the 

 pollen grains burst, but as the concentration increases, fewer 

 and fewer rupture until at 30 per cent this is entirely pre- 

 vented. The other sugars behave in the same general man- 

 ner as sucrose, but with less efficiency in preventing rupture. 

 With gelatin and gum arabic this sudden bursting ceases with 

 concentrations at 10 per cent and above, and then pseudo- 

 germination appears. 



The next trials were made with a series of combinations 

 or mixed solutions and the results of these tests are set forth 

 in table II. 



