10 BULLETIN 926, U. S. DEPARTMENT OF AGRICULTURE. 
was made by a first-generation female weevil that became adult dur- 
ing the latter part of June. This weevil lived a total of 67 days. 
The maximum length of life for the male weevils was also recorded 
for a first-generation weevil that became adult during the latter part 
of June. This weevil lived a total of 65 days. The average lon- 
gevity for hibernated weevils fed with sea-island cotton plantlets was 
11.05 days. The weevils lived 10.7 days on sea-island squares and 
15.3 days on green sea-island cotton bolls. By comparing the aver- 
age longevity of the weevil on sea-island cotton with the average 
longevity on upland cotton, it is clearly demonstrated that there is 
little, if any, difference in the food value of sea-island and upland 
cotton on the longevity of adult weevils. 
THE SIZE OF THE COTTON SQUARE ATTACKED BY BOLL 
WEEVILS. 
Male and female weevils feed largely on the cotton squares, except 
in the case of sea-island cotton, where there is a decided tendency 
to feed upon the bolls as well as the 
squares. Upland cotton squares grow 
very rapidly and there is little oppor- 
tunity afforded for direct feeding on 
the very small squares, except during 
the period when the first squares come 
on the plants and again when all 
Fic. 2.—Three sizes of sea-island cot- SQUares are punctured. However, 
ton squares chosen for oviposition by geg-island squares do not grow very 
the boll weevil. ° 
rapidly and a large number of the 
small squares are shed by the plant from feeding and egg punctures. 
It has been observed that a large number of undersized weevils are 
produced in sea-island cotton fields. These weevils are largely the 
result of eggs having been deposited in undersized squares, which re- 
sulted in an undersized weevil, owing to the lack of proper larval food 
(fig. 2). When a large number of sea-island squares are offered a 
female it has been observed that she invariably chooses the smaller 
squares for oviposition purposes. No records are available to show the 
length of the developmental period for weevils developing in under- 
sized squares on sea-island cotton ; however, it is not thought that there 
is much variation from that in large-sized squares. Observations on 
the size of weevils bred from bolls show that, except in the case of 
very young bolls which shrivel and dry very rapidly, nearly all 
weevils produced are of normal size. Sea-island cotton bolls seldom 
produce small-sized weevils, as the boll is very moist and. furnishes 
much better conditions for weevil development than upland cot- 
ton bolls. 
Yt 
