188 



CATERPILLAR PESTS. 



In every case of swarming caterpillars, the following is the 

 sequence of events that occurs. Under favourable circumstances a large 

 number of moths hatch at a particular time; very many emerge 

 from the chrysalides simultaneously and may be seen flying about 

 in the evening. These moths lay eggs; every female moth lays at 

 least a hundred and some lay as many as one thousand; if circum- 

 stances are favourable they all lay eggs within a few days. After 

 a week or so, the eggs hatch out and multitudes of caterpillars appear. 

 They are very tiny at first and feed steadily; if plentiful they devour 

 the plant they hatch on, becoming perhaps half grown; they then 

 commence to search for food and wander about; if large numbers are 

 hatched out, they then form into masses and if they find a crop they 

 will absolutely destroy it. 



When they have become full fed they descend into the ground 

 and become chrysalides, forming for themselves earthen cases in the 

 ground. All will perhaps disappear in a few days and the reports say 



that they have died; but 

 should circumstances be 

 favourable these chrysalides 

 will yield moths which will 

 again lay eggs, giving rise 

 to a fresh attack. 



Such is the usual 

 sequence; since the cultivator 

 only sees the caterpillars 

 feeding, he does not under- 

 stand the cause, nor does 

 he connect together the 

 appearance of moths and the subsequent swarms of caterpillars. These 

 attacks are worst when the conditions are such that the moths all 

 emerge from the chrysalides together. At the end of the cold weather 

 it becomes warm perhaps within a very few days ; then a vast number 

 of moths hatch out together; should the cold weather end early the 

 caterpillars attack the rabi crops, and the destruction may be very large ; 

 if the cold weather continues later the caterpillars may not find crops 

 to eat ; if it comes very gradually, the moths do not all hatch out at 

 once and the caterpillars do not come in swarms. If the caterpillars do 

 not come in swarms the wild plants may be sufficient for their food 

 and the crop will possibly not be attacked. Swarming caterpillars are 

 worst when they are so abundant at one time that they exhaust their 

 wild food-plants and are compelled to enter the crops to find food, 



Fm. 216. 



Moth of a common Swarming Caterpillar. 



