^ , J,] Farther Notes. 49 



13.— FURTHER NOTES ON INSECTICIDES. 



Plate IV, fig. 3, force pump ; fig. 4, a ordinary cyclone nozzle, b and c Termor el modifica- 

 tion of cyclone nozzle. 



A valuable paper on the "Green Scale Bug" (Lecanium viride), 



An Insecticide for the which has of late years done serious injury to 



"Green Scale Bug" of coffee cultivation in Southern India and Ceylon 



was published in 1886 by Mr. Ernest Green, 



who described the remedies that had up to'that time been proposed. With 



regard to these remedies, however, Mr. Green writes : — - 



*' In some cases their application is quite impracticable ; in many 

 others, whatever may have been the result with the old bug, 1 they have 

 absolutely no effect upon the new Green Bug/' 



In fact, up to that time, no satisfactory remedy for the pest had 

 been found. As, however, the insect, which attacks orange trees in 

 Florida, is closely allied to the Indian Coffee bug, it appeared probable 

 that the kerosine emulsions which are being used successfully in Florida 

 against the Orange insect 2 would prove equally applicable to the Coffee 

 Scale in India. 



In a paper, 3 therefore, which was published in the Journal of the 

 Agricultural and Horticultural Society of India, kerosine emulsion was 

 suggested for experiment against Coffee Scale. 



Results seem to show that the surmise was correct, and Mr. R. H. 

 Morris writes 4 : — 



" I have tried with great success an "emulsion of kerosine made with 

 common soap on the Green Bug, which has lately attacked coffee estates 

 in the Nilgiris. One part of the emulsion diluted with nine parts of 

 water, and sprayed over the affected coffee trees, kills the bug, whenever 

 it touches, at the first application/' 



The chief difficulty appeared to be to] obtain the proper apparatus 



for spraying the bushes with the insecticide, 

 Apparatus. , n • -i j- i 



r as the spray given by ordinary garden syringes 



was found to be far too coarse. Several American firms, however, 

 who manufacture apparatus for distributing insecticides, are now send- 

 ing their force pumps, &c, to the Indian Museum for experiment; while 

 amongst the many practical Entomologists in different parts of India, 

 who are in correspondence with the Museum, it is anticipated that there 

 will be no difficulty in getting the necessary experiments conducted in 

 order to ascertain which of these machines is best suited to the purpose. 



3 Lecanium nigrum. 



3 See Notes on Economic Entomology, No. 2, p. 5. 



3 On the work of the "United States Entomological Commission, by E. C. Cotea, Journ. 

 Agri.-Horti. Soc. lad., V d1. VIII, Part II, new series. 



4 In a letter dated '6th July 1888. 



E 



