It was thus clearly demonstrated that the abundance of adults was much less 
than in 1939 and that the parent population for 1941 will be considerably 
less than in 1940, when it was considered very small. Factors involved in 
this decline of adult 'populations are believed to have been weather unsuit- 
able for the development of the larvae and parasitization. 
Aestivation of Adults 
A few adults began aestivation as early as April 1, and small numbers 
followed throughout the month. The greatest number entered aestivation 
early in May and virtually all were in this state by mid-May. Emergence 
began late in November and apparently was complete by January 1, the greatest 
exodus occurring during the first half of December. The interval between 
earliest at.itivation and earliest emergence was about 7^ months, and this 
doubtless approximates the duration of the inactive period of most adults. 
Aestivating a»."ults congregated most conspicuously underneath the bark 
of growing trees and in trash piles affording the proper protective condi- 
tions. Large numbers also aestivated in date palms where scales and fibers 
of old leaf stalks provide almost unlimited facilities. Smaller numbers 
passed the summer and fall in the soil and debris about the base of trees, 
in heavily weeded areas, and in grassy ditch banks. A few undoubtedly sur- 
vived in other situations. None was found under the bark of dead trees or 
fence posts or in the cracks and crevices of open farm buildings. 
It would appear that the adults chose protected locations for aesti- 
vation in which there was a moderate amount of moisture with attendant modi- 
fication of the temperature. A disturbance of the proper balance of either 
moisture or temperature caused adults to abandon aestivation places and search 
for others. 
During the period of aestivation lasting throughout the late spring, 
summer, and early fall months adults did not feed under outdoor or indoor 
conditions. 
Studies of Sexual Development 
Dissections to follow the sexual development of male and female 
weevils v/ere begun late in April 1939 and continued almost weekly. These 
studies traced the sexual progress of adults during the period of aestiva- 
tion and after their migration to fields where all finally attained full 
maturity. 
Dissections of adults Juiuiv i^pril and May soon after they entered 
aestivation showed no development whatever of the sexual organs, and this 
condition continued until mi .''.-OctobGr. By that time an occasional male con- 
tained sperm in the testes, but all did not attain this stage until a month 
later. It v;as December before the first male reached full maturity and only 
one-third attained thitj stage by December 16. However, this small proportion 
of mature individuals among those still in aestivation was undoubtedly due to 
the constant departure from aestivation quarters after the middle of No- 
vember of the adults that were approaching sexual maturity. The de^'elopment 
