120 Indian Economic Entomology. [ Vol. I. 



" Caustic lime, applied in the form of whitewash, is fatal to every insect that it 

 actually touches, hut it is impossible by this means to exterminate every individual on 

 each tree ; and a few escaping would be sufficient to reproduce the pest within a short 

 time. The expense alone would make the work impracticable. Each separate coffee 

 branch mnst be turned over and the mixture applied with an ordinary whitewash 

 brush. A cooly is unable to finish more than twenty trees during the day; and 

 I have found that even then the pest shortly returns, as a proof that the work has not 

 been thorough. 



" Mr. Nietner, in his notes upon ' The Enemies of the Coffee Tree,' remarks that 

 ' the application of tar to the roots has been suggested, it being said that, taken up 

 into the system of the tree, it throws off the bug. Although hitherto no important 

 results have been achieved by carrying it out, this idea strikes me as a very valuable 

 one: it is through the root of the tree the evil should be dealt with ; but a substitute for 

 tar should he sought for, more powerful and more deadly to the bug, but at the same 

 time equally harmless to the tree.' 



" Following out this idea, I have tried the solution of phenyle, brought into notice as 

 an insecticide a few years ago. It is one of the extracts of coal tar, and probably con- 

 tains most of its active properties in a form that can be more easily taken into the 

 system of the tree. The mixture used consisted of one dessert-spoonful of phenyle to 

 two quarts of water. The soil round the root of the tree was thoroughly broken up 

 with a digging fork, and the liquid applied from an ordinary watering-can. My 

 experiment was limited to a single tree, and scarcely a sufficient time has elapsed to 

 judire of its success. But it has seemed to me that the pest upon the tree has been 

 gradually disappearing, although the surrounding trees have not altered their condi- 

 tion. 1 



" To the roots of another tree I applied half an ounce of napthaline (another extract 

 of tar), but I have not detected any beneficial effect in this case. 



" With the idea that an injection might be more rapid in its action, I drilled holes 

 with a half-inch auger into the stems of several trees, some of which I filled with com- 

 mon tar, others with pure phenyle ; but this treatment has produced no apparent result. 



" The Scale Bug being allied to the Phylloxera, which attacks grape vine, it is possible 

 that similar remedies might be effective. In the Tropical Agriculturist of February 

 1885, is au extract from the Planter s Gazette, which states that ' a means has been 

 discovered of overcoming the Phylloxera by an easy and inexpensive treatment, the 

 basis of which is an arsenical solution mixed with cinders. The limited experiments 

 made with this preparation seem to have been attended with admirable results.' 



" The following extract from an Indian paper describes a successful remedy for insect 

 blights upon paddy and other plants. I have been unable to obtain any of the Koonri 

 oil-cake in Ceylon, but it could possibhy be obtained from India for experiment. The 

 extract is as follows : — ' Mr. J. Dumaine lately suggested that fumigating with Mowha 

 oil-cake, if done immediately on the first appearance of insect pests while still affecting 

 small areas, might be usefully tried by tea-planters and others.' He was asked to com- 

 municate his own experience, and writes as follows : — ' Koonri oil-cake is made fiom the 

 seed of the mowha (Bassia latifolia), from which the oil has been expressed. I was 



1 December \31st. — After an interval of a month I now find that this tree lias entirely thrown off the 

 bupr, although on neighbouring trees the pest has rather increased than otherwise. 



13th July 1839.— Mr. Green writes : '* Please note that I am notlsatisfied that the phenyle treatment is of 

 any real value — other trials do not seem to have been equally successful — and the beneficial results, at first 

 net iced, may have been due to some other unsuspected cause. I think the kerosiue emulsion, used with 

 a really economical distributer, is the most promising remedy yet suggested; and I think this treatment 

 will be equally valuable for tea, to be used immediately after pruning, for the destruction of Aspidiotus and 

 other scale insects on the stems." 



