14 
BULLETIN 1374, U. S. DEPARTMENT OF AGRICULTURE 
Table 12. — Longevity of resting pink bollworm larvae 
Bolls of 1920 crop 
Date examined 
Number 
examined 
1921 
March 
April --- 
May 
June 
July 
August .- 
September... 
October 
November... 
December — 
1922 
January- 
February. 
March.... 
April 
May 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
300 
100 
600 
700 
Number 
of living 
larvae 
LOG 
48 
55 
52 
28 
9 
2 
2 
4 
1 
4 
1 
i 1 


Dead 
larvae and 
pupae 
15 
21 
25 
41 
46 
64 
14 
39 
64 
57 
73 
143 
50 
550 
481 
Per cent 
living 
87.90 
69.56 
68.75 
55.91 
37.84 
12.33 
12.50 
4.88 
5.88 
1.72 
5.19 
.69 
1.96 


Double seed of 1920 crop 
Number Number j Dead 
exan5nedi°; iivin S lar ^ an d 
larvae pupae 
100 
100 
100 
100 
100 
100 
200 
1,000 i 
975 
1 
o 
! 
1 I 
! 
196 , 
818 i 
750 
Per cent 
living 
29.89 
32.56 
16.09 
4.39 
3.26 


.12 

Maximum longevity 16M months. Maximum longevity 113^ months 
1922. 
This larva was placed in a pill box. It pupated and a perfectly developed moth emerged on Apr. 10, 
Some of the larvae in the bolls survived longer than those in the 
seeds. The larvae in both lots of material were attacked by mites ; 
which probably reduced the maximum longevity considerably. In 
obtaining the figure for maximum longevity given at the foot of the 
table, the date of the first killing frost in 1920 was used as the starting 
point. 
Table 13 gives the results of the examination of bolls and seed of 
the 1921 crop. The bolls were gathered in the field on November 11, 
1921, and stored on the veranda of the laboratory in sacks. The 
seed came from cotton picked on November 1 and ginned November 
4, 1921. Part of this was stored in sacks in a warehouse, and was 
examined later as a whole. Other parts were stored over winter in a 
seed house and in a railroad car, and in the spring the double seed 
were picked out and stored in glass jars in the laboratory. 
Table 13. 
— Longevity of resting pink bollworm larvse 
Bolls of 1921 crop 
Seed of 1921 crop 
Date examined 
Number 
examined 
Number 
of living 
larvae 
Dead 
larvae 
and 
pupae 
Per cent 
living 
Quantity! dumber 
examined, °\£™ s 
Dead 
larvae 
and 
pupae 
Per cent 
living 
1921 
100 
15 
30 
100 
95 
67 
60 
140 
135 
175 
449 
700 
1,100 
1,200 
296 
51 
39 
93 
. 29 
2 

1 
1 
1 
1 
1 
1 
1 
8 
6 
14 
59 
71 
97 
116 
299 
352 
403 
836 
1,366 
2,945 
3,184 
97. 37 
89.47 
73.58 
61.18 
29 
2.02 

.33 
.28 
.25 
.12 
.07 
.03 
.03 
Ounces 
1922 
8 6 
7 2 
1.6 | 1 
6.5 1 1 
2.0 1 1 
25.5 1 
94 
99 
218 
99 
3,608 
3,382 
2,000 
1,057 
10,564 
1,658 
6 
July 
1.98 
.46 
1 
.03 
.03 
14 
7 
58 
9 
1 
1 
1 

.05 
1923 
January 
.09 
.009 
March 
.0 
N9TE— The first four lots of seed examined consisted of both single and double seeds; the remaining lots 
consisted entirely of double seeds. 
