186 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XV. 



is to sprinkle the Insects with creosote oil, the oil known as ' l'huile 

 lourde' in the trade. This effectually destroys them while at the same 

 time diminishing the terrible stench which will arise from the bodies if 

 the flail is used. The liquid as obtained from the trade is first mixed 

 with Is time3 its weight of water. 



3. After formation into column. — Dig long dry trenches in the 

 path of the columns, one to two feet in depth, and of the same width 

 and drive the locusts into these. Parties of men, women and boys, 

 armed with branches, etc., can do this, whilst men line the far edge 

 of the trench and throw in earth and bury the insects. As soon as 

 one trench is filled the hoppers can be made to wheel to another and 

 the performance be repeated. Creosote oil, sprinkled in the trenches, 

 will prevent the terrible stench. The earth should be well trampled 

 down to prevent any young locusts escaping. When the hoppers have 

 attained some size this plan can no longer be used as they are then 

 able to hop out of the trenches. It will be found that at this period, 

 when disturbed in the open, they retire to the nearest cover and 

 remain there. Dry material available in the neighbourhood should be 

 collected and spread in patches or long strips. The locusts are then 

 driven into this ambush, surrounded by the people and the patches set 

 on fire. Whole swarms can thus be wiped out. A more expensive 

 plan for annihilating them at this period is by the use of what is known 

 as the ' Cyprus screen ' system which is as follows : — 



Cloth screens, about 3 feet high and bound at the top with a strip 

 of oil cloth to prevent the locusts from climbing over, are erected 

 in advance of the swarm, pits being dug close to the screens, at right 

 angles to them and on the side of the swarm. The edges of the pit are 

 protected by frames made of cloth and wood with a zinc edge arranged 

 to prevent the young locusts from climbing up and escaping from the 

 pits. A swarm on arriving at the screen invariably turns to the right 

 and left along it, apparently endeavouring to go round it and thus fall 

 into the pits and can be destroyed wholesale. The cultivator will often 

 probably find the simple dry ditch (for young hoppers) and the brush- 

 wood and bush systems (for older ones) the best, but the screen system 

 is undoubtedly the one to employ when stations are in danger of inva- 

 sion from large hordes of this pest. To this end there should be kept 

 in store in all large civil stations and cantonments a few sample screens 

 and trench frames as patterns. From these, when a serious invasion was 

 imminent, the extra number required could be easily knocked up. 



