PROCEEDINGS OF THE SECOND ENTOMOLOGICAL MEETING 223 
Oil Emulsion to twelve annas. Fish-oil-Resin Soap is more effective 
and cheaper than Crude Oil Emulsion. 
The relative cost will depend largely on the freight charges. The mp, Fletcher. 
Fish-oil Soap is made in Malabar, whereas the Crude Oil Emulsion has 
to be got from Calcutta. In any case, eight annas per tree seems rather 
expensive. 
The cost is very gladly borne by the owners of the trees. because Mr. Ramakrishna 
the crop is very valuable. Ayyar. 
What sort of sized trees were these ? How far were they apart ? Mr, Fletcher. 
The trees are ten to twelve feet apart, and twenty to twenty-five yy, Ramakrishna 
feet apart in some cases. Spraying is practicable in groves where the Ayyar. 
trees are not very big and the crop is valuable. ; 
What items are included in the estimate of cost ¢ The cost will Mr. Fletcher. 
vary greatly with the labour required, as, for instance, if water has to 
be brought from any distance. 
Nothing was included on account of labour charges, as the labour yy, Ramakrishna 
was provided by the gardeners, who were employed in these gardens Ayyar. 
in any case and were detailed to do this work., The estimate only 
includes cost of the insecticides used. 
Will you tell us about your experiments with Idiocerus in the Punjab ? Mr. Fletcher. 
In the Punjab experiments against mango-hoppers were carried out yy, M. M. Lal. 
at Hoshiarpur. We tried three methods: (1) spraying with Fish-oil- 
Resin Soap and (2) with Crude Oil Emulsion, and (3) smoking the 
hoppers out by lighting smoky fires under the affected trees. Of these 
Fish-oil-Resin Soap was found very effective ; when used at a strength 
of one pound in 15 gallons, the hoppers were killed. Crude Oil Emul- 
sion was effective when used at a strength of one pound in eight or nine 
vallons of water. Smoking did not seem to have any good effect ; only 
the winged hoppers left the trees temporarily. 
Spraying was continued until the fruits had set. The fruit on the 
sprayed trees set very well but in the surrounding areas the trees did 
not bear any fruit. Later on, the young fruits were attacked by these 
hoppers and many fruits dropped off the trees. 
The experiments are being repeated this year. 
The Mysore Agricultural Department has suggested to take a large Mr. Kunhi 
screen smeared with a sticky substance and carry it about, driving the Kannan. 
hoppers from the trees, so that they will stick to the screen. This 
should be done early in the season. 
That method does not seem to be very practicable. I should not Mr. Fletcher. 
care to try to carry about a large sticky screen on a windy day. 
