AND ITS RELATION TO ANIMAL LIFE 143 



fumigated with cyanide of potassium. Mr. 

 Kemp is so satisfied with my views that he 

 intends remanuring his trees. 



I would like to mention here that there is 

 no tree so easily killed from over- manuring 

 as the orange tree, and farmers should be very 

 careful on this point. 



Another fruit that suffers greatly from 

 chlorosis in South Africa is the pineapple, so 

 much so that in many cases it is not worth 

 eating. 



This fruit is also largely damaged by para- 

 sites, including the locust. While writing on 

 chlorosis of plants I cannot conclude without 

 mentioning the yellows, a fungoid disease that 

 destroys thousands of peach trees in America 

 every year. 



As it is admitted a weak solution of sul- 

 phate of iron turns the leaves green, and that 

 nitrates have the same effect, and as iron and 

 nitrogen are distinct poisons to the fungi, it 

 appears reasonable to think any chemical 

 compound that would keep the leaves green, 

 and that at the same time would be a natural 

 poison to the fungus, would prevent the trees 

 from dying of this disease. 



