396 SOUTHEBN FIELD CROPS 



or young fruits, of the -cotton plant are due both to punc- 

 tures made by the mature weevils for the purpose of ob- 

 taining a food supply for themselves, and to the young 

 grubs, which develop within the square or boll where the 

 egg has been laid by the mature weevil. 



A few days after an egg has been laid in a square, the 

 color of the latter becomes paler, and the surrounding leafy 

 parts flare, or spread outward (Fig. 173). The square may 

 remain hanging on the plant or it may drop to the ground, 

 carrying the larva or grub within. It was found in experi- 

 ments in Texas that among the immature insects in the 

 fallen squares, about one third developed into adult weevils. 

 The remainder were killed by their insect enemies or by 

 the rapid drying of the squares where they lay in strong 

 sunlight on the hot soil. 



The dead squares that continue to hang to the plants 

 bring forth a larger proportion of mature weevils than 

 do the fallen squares, probably because in the hanging 

 squares larvae are less exposed to the attacks of their 

 principal insect enemies, the ants. Hence some farmers 

 attempt to brush off as many of these infested squares as 

 possible, by attaching a brush, or a stick wrapped with 

 cloth, to the cultivating implement. Some authorities 

 regard this as impracticable. 



The larvae developing within the bolls may result in 

 the destruction of only one lock or of the entire boll. 



Feeding punctures may cause the square to die or the 

 boll to rot. 



365. Rapid multiplication. — One of the reasons why 

 the cotton boll-weevil is destructive is because it multi- 

 pUes very rapidly. The time from the laying of the eggs 



