141 



ground some of the burrows are so large as to enable a man 

 to insert Ms hand. They are often of considerable length, 

 several feet, and their depth varies a great deal, but seldom 

 exceeds 18 inches below the surface. 



In an infected area holes partially stopped up may be 

 noticed. These are holes leading to burrows where it may 

 be safely concluded that crickets are contained. To con 

 tinually dig out these crickets costs a great deal of time and 

 labour and it will be found that the Carbon bisulphide ap- 

 plied in the following way is most effective and very cheap. 

 1 have treated 108 holes in 1 hour 20 minutes having to find 

 and clear the holes myself. 



Three coolies is a useful number to treat the holes. 

 One man to go in front and mark the holes the other two 

 to apply the poison. 



Take a piece of cotton wool about the size of an or- 

 dinary thimble and soak this in the Carbon bisulphide, in- 

 sert quickly into the hole, and close with some of the 

 surrounding earth. As the efficacy of the application 

 depends on the distribution of the gas through the burrow, 

 it is advisable to dig away a little of the earth surrounding 

 the entrance hole, so as to make a clear space for the in- 

 sertion of the cotton wool. A small knife is the best im- 

 plement for this purpose. When treating an infected field 

 the coolies must be made to treat the holes systematically 

 in order to insure the Carbon bisulphide being contained 

 within the burrows. Treatment of holes here and there is 

 useless as the gas escapes through other exits and further 

 the cricket is able to retreat. 



There is no necessity to close the entrance very tightly 

 as by so doing one is liable on a sandy soil to stop up the 

 passage behind the cotton wool which is disastrous. 



Coolies must be informed that Carbon bisulphide is a 

 very dangerous substance if any light is brought close to 

 it, further the bottle must always be kept corked otherwise 

 a great deal of the liquid will evaporate. 



The best time to apply the Carbon bisulphide is be- 

 tween the hours of 4 to 6 p.m. 



H. C. Pkatt. 



Note. Notes on the Brachytrupcs have already ap- 

 peared in the Bulletin (see Vol. IV. 457 ; Vol. V. 69). 



The animal is very abundant in the Singapore Botanic 

 hardens and is often to be seen in and about the rubber, 

 but as there is plenty of grass about it does no harm, cou- 

 tently itself with eating grass blades. 



