BIOLOGY OF THE MEXICAN COTTON 
BOLL WEEVIL. 
23 
TaBLeE XII.—Summary of development of first generation boll TEBE AS under 
field conditions on upland cotton. 
Date of oviposi- 
tion. 
May 29-Junel...- 
May 29-June 21. . 
May 29-June5. - - 
Junel-Junel4... 
June2-June 8s... 
June 8-Junel5.. 
June9to Junels. 
June6-Junel4... 
June8-Junel9_.. 
Junel2-June21.. 
June12-June23.. 
Junel1s—June 22... 
Toth. 2. 
Weighted aver- 
age. 
Date squares 
dropped off. 
Date hatched. 
| 
Totalnum- | 
ber weevils 
bred. 
June 6 June 25. 
June7-July 8. -- 
June 9-June 16. 
Junell—June 24 
Junell—June23 
June 16—-June30 
June1s—June23 
Junel7—July 1.. 
Junelé—June 30 
Junels—July 4. . 
June19-July 8. - 
June30-July 8.. 
June17—June 25. 
June 12-July 10. 
June 20-June 25. 
June 20-July 5.. 
June22-June25. 
June 30-July 5.. 
July 2-July 5. - 
July 3-July 9- - 
July 1-July 5-- 
July 5-July 10. - 
July 2 July Hae 
July 11-July 13- 
8 6 | 
15 7 
‘2 3 | 
8 3 | 
2 0 | 
5 4 | 
1 3 | 
7 3 
Sa Ga 
6 ae 
5 7 | 
4 5 
73 52 | 
Average period of | Aver- 
development. | Mean| Mean) 28°. 
C * | maxl- 
air | soil 
hue | tem-| MUD 
| mid- |pera- ie E 
-| On On | To- | ity. |ture pend 
ee ground.} tal. Bee 
Days.| Days. |Days.| 
| 11.6 WEI) DAG IGS eby Rae) Tan oe 
11.2 10.8 | 22 72.2 | 82.3 | 101.6 
10.8 9.4 | 21.2 |65.2 | 85.5 | 109.7 
11.2 12.7 | 238.5 76.3 | 81 | 101.6 
11 10.5 | 21.5 |62.5 | 85.5 | 109.7 
10.1 12.2} 22.3 |76.3 | 81 | 101.6 
11.5 11.0 | 22.5 |76.3 | 81 | 101.6 
10. 3 13.7 | 24 75.96 | 81.4 | 101.3 
10.4 13.3 | 23.7 76.3. | SL 101.6 
9.3 12 21.3 |77.2. | 82.3 | 101.6 
12 11.8 | 23.8 |79.2 | 82.8 | 101.2 
12.5 9.4 | 21.9 |79.2 | 82.8 | 101.2 
| 
10.9 11.4 | 22.4 73. 51 | 82.6 | 103.7 
DEVELOPMENTAL PERIOD OF FIRST GENERATION BOLL 
WEEVILS ON SHORT STAPLE UPLAND, SEA-ISLAND, AND 
LONG-STAPLE UPLAND COTTONS UNDER FIELD CONDITIONS. 
In addition to the series of hibernated female weevils under obser- 
vation a series of first generation weevils was used to determine the 
difference in the length of the developmental period under field con- 
ditions on upland, sea-island, and long-staple cottons. 
The first generation female weevils deposited eggs at an average 
rate of 7.6 eggs per day on sea-island cotton. The maximum number 
of eggs deposited during any one day in sea-island cotton squares 
was 29. 
The 10 female weevils under ahcecuabion on long-staple cotton 
squares deposited eggs at an average rate of 6.3 eggs per day. 
The 
greatest number of eggs deposited during one day in long-staple 
squares was 21 eggs. 
On upland cotton the 10 female weevils deposited eggs at an aver- 
age rate of 6.2 eggs per day, with a maximum of 23 eggs deposited 
by a single Sonnet during one day. 
On upland cotton the infested squares remained on the plants for 
A period of 11.4 days was the 
an average period of 10.9 days. 
average time required to complete the development of the immature 
stages after infested squares dropped off the plant. 
The average number of days elapsing from the date of eg 
ture to the falling of the infested squares 
The average number of days required to complete the de- 
cotton. 
was 10.7 
g@ punc- 
on sea-island 
