116 Indian "Economic Entomology. [Vol. I 



The following is Mr, Jackson's account of the treatment he has 

 adopted; it was published in the Ceylon Observer of 17th June 1889 : — 



" I have already gone through a deal of correspondence about my treatment for 

 Green Bug, and a good many have been over at different times and seen the results for 

 themselves. 



" I read the letter of Mr. Cotes with much interest and was quite prepared to hear 

 that the ' Kerosine Emulsion ' had destroyed the bug wherever it was applied ; but I 

 have certainly no experience myself beyond this : — nothing that I have tried has suc- 

 ceeded by first application in both destroying the bug and keeping it away for the 

 future. With me it has regularly returned each season fat and flourishing ; but I am 

 glad to say it has not spread so rapidly or to the same extent the last two seasons as 

 previously, and that the trees treated for bug seem to stand the attacks better now 

 than at first ; and I think it probable that the pest will gradually leave us. I notice 

 you say that ' good results were obtained for a time, yet experience did not prove it to 

 be such a case as would warrant general application or repay all the outlay.' I really 

 do not know how you arrive at such conclusions ; for, whatever doubt there may have 

 been in the early experimental stage, there can be no doubt now that the treatment 

 carried out on these estates has been very successful. The cost has been anything but 

 excessive and perhaps much less than many would think. 



" The first year's cost was the heaviest, and I give actual figures of this on one of 

 the estates as follows :— - 



"187 acres, a lot of coffee besides in tea: — labour cost Rl,32281 ; lime cost 

 R45339 ; kerosiue oil and soap, <&c, cost R82'98 : total Rl^'lS. 



" On another estate it was — 98 acres, and a lot of coffee in tea : — labour cost 

 R71027 ; lime cost R42871 ; kerosine emulsion cost R59'01 : total Rl,197-97. 



" This is for the full twelve months, which means two general attacks upon all 

 affected trees right through, and then several gangs of coolies being kept on to watch 

 for any return of the bug and to wash it off wherever it appears. 



" This year the cost is considerably less. The lime is altogether an extra, but I 

 have found it very beneficial to the trees after being treated for bug, and it helps both 

 to ripen up the crop and to keep up the condition of the tree. The above 285 acres are 

 well-cultivated coffee, and have been regularly manured. I found, however, that the 

 highest cultivation of itself could not withstand the severe attack of bug which we had 

 at first, and that equally good coffee, side by side with these 187 acres and 98 acres, to 

 which we did not apply the kerosine emulsion, but which had extra manuring, utterly 

 failed to keep its condition or to ripen its crop to any extent. 



" The appHcation in my case is a very simple one. The cooly has a rough piece of 

 cloth which he soaks in the kerosine oil mixture and rubs over the bug wherever it is 

 to be found (I do not wash the stems of the trees), and this means sudden death. In 

 the .early life of the young bug, I have found even water will remove it ; but when 

 older, it takes a good strong rub to unhinge it. The details of application are easily 

 worked out, each one for himself. I believe a great deal of valuable coffee might 

 have been saved had the kerosine emulsion been carried on more generally. 



" The difficulty at present is to spare labour with such demands as tea makes upon 

 us just about the time that the bug begins to put in an appearance : so that any plan 

 giving equally good results, which could reduce the labour required, even at an in- 

 creased cost, might be valuable." 



The following- is Mr. Green's account of Scale insects in connection 

 with coffee; it was published in Ceylon in 1886, and is reprinted here, 



