INSECTS INJURIOUS TO COTTON 265 



particularly in the tender terminals, and as soon as squares are 

 formed the females commence to lay their eggs in them. Each 

 female lays an average of about 140 eggs, laying four or five a day. 

 The female drills a small cavity in the square and in it deposits 

 a small oval white egg, which hatches in about three days. 

 The grub feeds upon the embryo flower, which usually fails 

 to develop, and the infested square generally falls to the ground. 

 In from seven to twelve days the larva is full grown and changes 

 to the pupa, which stage lasts from three to five days. Thus 



FIG. 195. The cotton boll weevil, larva and pupa enlarged. 



from egg to adult requires from two to three weeks, though 

 climatic conditions cause considerable variation in the length 

 of time. The larva is a footless, white grub, with brown head, 

 which lies curled up in the square as shown in Fig. 195, where 

 the soft white pupa is also found. The adult weevils feed entirely 

 during the day. Their length of life depends upon various 

 conditions, but in the summer season the majority do not live 

 over sixty days, while during the cooler part of the year those 

 which hibernate live five or six months. Many squares are 

 destroyed by the feeding punctures of the weevils. " The males 

 feed upon the squares and bolls without moving until the food 

 begins to deteriorate. The females refrain from depositing in 

 squares visited by other females. This applies throughout 

 most of the season, but late in the fall, when all the fruit has 

 become infested, several eggs may be placed in a single square 



