bt 
bo 
hatches under normal conditions in about 3 days and the grub im- 
mediately begins to feed. In from 7 to 12 days the larva or grub 
(fig. 3, at left) passes into its pupal stage (fig. 3, at right), corre- 
sponding to the cocoon of butterflies and moths. This stage lasts 
from 3 to 5 days. Then the adult issues and in about 5 days begins 
the production of another generation. Climatic conditions cause 
considerable variation in the duration of the stages, but on an aver- 
age it requires from 2 to 3 weeks for the weevil to develop from the 
egg to the adult. Males and females are produced in about equal 
numbers. The males feed upon the squares and bolls without moving 
until the food begins 
a | \ to deteriorate. The fe- 
ny . males refrain from de- 
positing in squares vis- 
ited by other females. 
This apples through- 
out most of the season, 
but late in the fall, 
when all the fruit has 
become infested, sey- 
eral eggs may be placed 
in a single square or 
boll. As many as 15 
larvee have been found 
ina boll. The squares 
are greatly preferred 
as food and as places 
for depositing eggs. 
As long as a large 
supply of squares is 
present the bolls are 
ic. 5.—Cotton square showing boll weevil in position. not damaged to any 
Natural size. (Author's illustration.) serious extent. The 
bolls, therefore, have a fair chance to develop as long as squares are 
being formed. Whenever frost or other unfavorable weather causes 
the plants to cease putting on squares the weevils attack the bolls. A 
conservative estimate of the possible progeny of a single pair of 
weevils during a season beginning on June 20 and extending to 
November 4 is 12,755,100. 
The cotton boll weevil, as far as known at present, has no food 
plant other than cotton. This has been determined by planting 
various plants related to cotton in the vicinity of infested cotton and 
in cages in which weevils were placed. It has therefore been demon- 
strated beyond any doubt whatever that the insect is restricted to the 
344 
