INSECTS ON THE FARM 307 



beetles feed on the foliage, and as soon as the squares are 

 formed the females lay their eggs within them ; as the grubs 

 develop, the squares usually fall to the ground. The grubs 

 pupate within the squares, and soon a second generation of 

 adults is out. The time from egg to adult, with favorable 

 climatic conditions, is from two to three weeks. Four or five 

 generations of these insects are produced in one season. The 



FIG. 154. Effects of the cotton-boll weevil 



The larva of the boll weevil is shown in the center of a bud or square, and of a boll ; 

 it destroys the central part of both 



female beetles prefer the square, but when squares are no longer 

 available, eggs are laid in the bolls. 



In some localities the migration of the adult boll weevils 

 begins by the middle of August. However, it is the great dis- 

 persion of the early fall which carries the insect far into the new 

 territory. It is gradually spreading over all the cotton-producing 

 states. With the advent of cool weather in the fall the adult 

 weevils in the cotton fields seek protection against the winter 

 and thus fly from the fields in every direction. They may hiber- 

 nate in hedges, woods, cornfields, haystacks, farm buildings, 

 and in trash and weeds in the cotton fields. 



