56 



drought. In districts subject to a heavy southwest monsoon, the 

 pest is at its height from the middle of March to the middle 

 of June, when it is checked by the continuous rains. There is a 

 recrudescence from September to January, when it again de- 

 creases during the dryest months. On the other side of New^ara 

 Ehya, I am informed that the bug usually appears towards the 

 end of April, and reaches a climax in October or November. If 

 there is any very wet weather in the mean time, it temporarily de- 

 clines, but flourishes in times of light rain wath intermediate sun- 

 shine, and disappears almost completely from December to April. 

 "The periods of decrease are marked by the death of fully 90 

 per cent, of the insects from an epidemic fungal disease. The 

 scales shrivel and become covered with a greyish-white fungus, 

 which extends as a delicate fringe all round them. Dr. A. Zim- 

 mermann, then of the Botanic Gardens, Buitenzorg, Java, de- 

 scribed this fungus under the provisional name of Cephalosporiiim 

 lecanii in one of the circulars of his department. Dr. Zimmer- 

 mann informs me that he has been experimenting with this fungus 

 with a view to obtaining a culture that can be applied as a spray, 

 but I have not yet heard whether success has attended his at- 

 tempts. In Ceylon the fungus seems to be widely distributed, 

 but depends upon climatic conditions for its proper development. 

 It appears to be readily communicable by direct contagion in Cey- 

 lon. But material sent to Mr. Newport, in Southern India, 

 failed to induce the disease in 'Green-bug' there. The weather 

 in India at the time was not favorable for the experiment. I am 

 inclined to think that this grey fungus has been gradually in- 

 creasing and that its effect in reducing the numbers of the bug !s 

 more marked year by year, * * =1: >k * 



"From the sudden appearance of the pest and its rapid ex- 

 tension, it is almost certain that the insect is an introduced species, 

 and it seems probable that the Libernian coffee plant may have 

 been the vehicle of introduction. Lccanium viride has recently 

 been recorded from Africa by Mr. R. Newstead from Lagos, 

 West Africa. It is true that Mr. Newstead considers that the 

 African insect is a distinct variety, but scarcely sufficient ma- 

 terial was examined to establish that fact." 



Granting that Hcinileia vastatvix w^as principally responsible 

 for the devastation of coft'ee in Ceylon, it does not follow that 

 Coccus z'iridis could not have accomplished the task unaided. In 



