214 PEOCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 



Both young and old trees are attacked. Young trees are hollowed 

 out from top to bottom. The grub throws out dust from its galleries. 

 We tried to probe a gallery but the probe went upwards. Kerosine 

 does not kill the grub ; we gave one 'grab three dippings in kerosine and 

 yet it survived and pupated. In one locality there are 3,000 jak trees 

 and all are affected by this beetle. 



I have found it spreading throughout the valley in some parts of 

 Sylhet. The older trees can withstand the attack but the young trees 

 do not grow. We find fifty per cent, of the trees attacked. The trees 

 are not killed but are damaged severely. The tunnels of the grubs are 

 very pecuUar. I tried the effect of carbon bisulphide on five trees and 

 it was very satisfactory. I closed the side holes with mud and injected 

 the carbon bisulphide through one hole. This remedy, however, cannot 

 be adopted by the cultivators. Kerosine is not effective. 



Kerosine is not sufficiently 'volatile. You might try benzine, as 

 that is more volatile and it is readily obtainable from Digboi. 



I tried phenol and carbon bisulphide in the case of a borer in lime. 



One could use a White Ant Exterminator and pump in the gas. 



Or you could use chloroform and creosote and inject it with a long- 

 nozzled syringe. 



Any volatile hquid of that kind should be effective. 



With a White Ant Exterminator we can inject fumes of sulphur 

 and arsenic and then see where the gas comes out and close the holes and 

 then pump more gas in. 



I do not think the AVhite Ant Exterminator would be a practical 

 proposition. For one thing the gas must be injected hot or it will all 

 condense without doing any good. 



What girth are the trees attacked ? 



Various girths. The grub bores down the stem and in big trees the 

 young branches are attacked and the grub works its way do\vn. The 

 grub comes to maturity after two years. 



Cwlosterna »p. 



This insect was reported to us from Manipur State, where considerable 

 damage was done to mulberiy on one plantation. " A quantity of 

 wood-dust accumulated around the roots. Holes appeared here and 

 there in the stem. Now when the tree is cut down it is found to be hollow 

 and to contain these beetles and larvae." (Letter from Vice-President, 

 Manipur State Darbar, Imphal ; 27th April 1914.) No specimen, however, 

 is traceable. 



An unnamed Ccelosterna is also referred to in Ind. Mus. Notes. V, 

 iv, 213 as doing much damage to mulberry at Shahdera, near Lahore. 



