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treatment for half an hour only, at the end of which time the case was thrown open. As a check on the experiments 
sprays of plants with living Ortliezia insects (lantana-bug) were included. In each case the result was most 
satisfactory. Every insect was killed and not even the most delicate plant was appreciably injured. Jt is important 
that the treatment should be conducted after sunset : 5.30 to 6 p.m. is the best time. On subsequently examining the 
plants treated (which had just arrived from England) two notable scale-insects — not yet established in Ceylon— were 
found, viz., Lecanium hesperidum (the scale of the orange tree), and P alviaaria Jioccifera (an enemy of Camellia 
plants). Both these insects would probably flourish in this country, the former on Citrus trees of all sorts, the latter 
on tea (a close ally of the Camellia). Fortunately the insects had been killed by the treatment. The plants have 
since been under observation, but no fresh attack has occurred. 
Xyleborus forntcatus, the "shot-hole borer," still attracts attention and has been recorded from several fresh 
locaiities. Where attention is paid to the destruction (by burning) of prunings in affected fields, the pest can be kept 
within bounds, though it is practically impossible to exterminate it. 
Orthezia insignis (lantana-bug) is still rampant. It has firmly established itself as a garden pest, where its 
presence causes the disfigurement of some of our most ornamental shrubs. Cases of its sudden appearance on small 
plots of tea have been reported ; but prompt measures (pruning and burning) have been successful in eradicating it 
in such situations. No natural enemies have been observed. Nothing seems to relish the Orthezia. 
The damage caused by White Ants (termites) in Ceylon and the cost of preventive measures to safeguard 
timber is recognized to be enormous. From its subterranean habit it is difficult to fight against this destructive pest. 
But this very habit would lend itself to the bisulphide of carbon treatment. The fumes from the bisulphide are 
heavier than air and sink to the bottom of any receptacle or hole. It is a well-known means of destroying wasps in 
their nests ; it is tlie most effective way of reaching weevils and other insects in large masses of grains ; and it is 
coming largely into use in parts of the United States to destroy rats and ground-squirrels in their holes. For white 
ants all that would be necessary would be to soak pieces of tow in the liquid and place them in the principal entrances 
oc the ant-hills or burrows, block up all the holes, and leave the fumes to do their deadly work. Unfortunately 
carbon bisulphide is not obtainable in Ceylon. Owing to the inflammable nature of the fumes the Shipping 
Companies will not accept the risk for the sake of the small quantities required. I have been unable even to obtstin 
a sample for experimental purposes. If it could be shown to be a certain means of exterminating white ants, large 
quantities of the chemical might be employed, and it might be possible to obtain supplies by some of the coasting 
steamers that now carry other explosives, paraffin oil, &c. 
Many scale-insects in Ceylon are subject to various Epidemic Fungal Diseases which serve to keep them in check. 
With the assistance of Mr. John Parkin, of Cambridge, the different species of these entomophagous fungi are being 
studied, and cultures are being propagated with a view to their possible use against other scale i ests. 
Collections of Coccidce have been sent in for determination from India, Mauritius, Java, and Australia, 
Various other insect pests have been received from the planting districts of South India for examination and report. 
In conclusion, I must earnestly ask for the assistance of planters and all agriculturists in the collection oi 
specimens, observations, and all data connected with insect pests. Without such assistance it it impossible t( 
efficiently carry on the work of the Department. I am frequently informed that such and such a product has beer 
attacked by some insect ; but that specimens were not sent in, as it was probably one that I knew all about, and tha 
I must be overwhelmed with such letters and material. I would therefore impress upon planters that reports of eacl 
attack of even the commonest insect pest should be sent in to the Department, accompanied, whenever possible, b; 
specimens. Such reports are filed and the specimens preserved and registered for future reference. This materia 
will be of the greatest value, in determining the times and seasons and the distribution of the various injuriou 
insects. 
12. — Laboratory and Herbarium. 
The present laboratory has been occupied during the year by the following workers : — Ml 
Parkin, from January 1 to April 14 ; Mr. A. K. Coomaraswamy, at intervals from January 1 to Marc| 
5 ; Professor K. Goebel, of the University of Munich, from January 22 to February 9 ; Mr, E. 
Goodrich, of Oxford University, from July 11 to July 18 ; Mr. E. M. Wilcox, of Harvard Universitj 
from September 19 to November 1 ; Mr. E. E. Green, from October 7 to December 31 ; Dr. A. PreyeJ 
of Berlin, from November 21 to December 31. Mr. Parkin was chiefly engaged in investigations in^ 
the methods of coagulation of indiarubber milks, the preliminary results of which have already bee 
published in the circulars. Mr. Coomaraswamy was chiefly engaged in the collection of material fd 
teaching purposes ; Professor Goebel collected a considerable amount of material of various kinq 
for further study in Europe ; Mr. Goodrich was occupied in zoological study, Mr. Wilcox and 
Preyer in investigations of various points in economic botany. The Director was engaged in mar 
economic studies, and in completing the monograph of the Podostemacece ; these studies were co\ 
tinned during the summer in Kew and Paris. 
Peradeniya, January 30, 1900. 
JOHN C. WILLIS, 
Director J 
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