The L eaf Disease. 273 



visitation will be appreciated, when it is stated that 

 the yearly crop of Ceylon has been diminished some 

 300,000 cwts. since its appearance. 



Hopes are entertained that the disease is now on 

 the decline, but whence it came, and what are the 

 conditions under which it finds most encouragement, 

 appear to be questions as to which nothing is known 

 with anything approaching to certainty. The idea 

 in one place that the visitation is caused by, or at 

 least connected with, drought, or an exposed situa- 

 tion, is immediately disproved by its appearing, 

 with equal destructiveness, in some sheltered valley 

 where moisture abounds. On the whole, however, 

 the weight of evidence, so far, seems to favour the 

 conclusion that the disease is most prevalent in 

 dry, exposed situations, with poor soil, and where, 

 consequently, the trees are weak in constitution ; 

 while there is even great unanimity of opinion that 

 its ravages, though not altogether prevented by 

 high cultivation, may be at least checked by it. By 

 the term "high cultivation," I mean careful pruning, 

 manuring, shade, where required, the entire sup- 

 pression of weeds, &c. 



A Bombay paper states that coffee-leaves from 

 Mysore have been submitted to the Royal Agricul- 

 tural Society, affected with a new kind of fungus, 

 different from that which is above described, and 

 to which the name of Pellicularia Koleroga has 



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