132 BULLETIN 1476, U. S. DEPARTMENT OF AGRICULTURE 
Table 42. — Survival of Pyrausta nubilalis larvae and pupae in water — Con. 
Materials 
Date 
placed in 
water 
(1920) 
Date 
removed 
(1920) 
Du- 
ra- 
tion 
pe- 
riod 
Num- 
ber 
of 
speci- 
Per cent 
alive 
mens 
4 
100 
2 
50 
11 
None. 
5 
(A) 40 
5 
(B) 20 
5 
(C) None. 
5 
(D) None. 
20 
(E) 25 . 
5 
(A) 100 
5 
(B) 40 
5 
(C) 10 
5 
None. 
5 
None. 
5 
(D) 80 
11 
(E) 54. 5 
14 
(F) 7. 1 
25 
40 
10 
90 
10 
60 
10 
60 
10 
None. 
30 
3.3 
10 
None. 
10 
80 
10 
60 
10 
10 
10 
None. 
5 
None. 
5 
None. 
5 
None. 
5 
None. 
50 
24 
Remarks 
Cornstalks submerged in fresh 
water. Weighted down in 
large wire-screen cage. Sec- 
ond-generation larvae. 
Cornstalks submerged in sea 
water in glass cylinder. 
Held in place with weighted 
gauze. Second generation 
larvae. 
Cornstalks floating in sea 
water in glass cylinder. 
Tanglefoot at edge of water. 
Second-generation larvae. 
Free larvae submerged in fresh 
water in wire-screen cages. 
Second-generation larvae. 
Cornstalks submerged in sea 
water in wire-screen cage. 
First-generation pupae. 
Cornstalks floating in sea 
water 1 week. First-gen- 
eration pupae. 
Cornstalks floating in fresh 
water. First-generation 
pupae. 
Free pupae submerged in sea 
water in wire-screen cages. 
First-generation pupae. 
Free pupae submerged in fresh 
water in wire-screen cages. 
Second-generation pupae. 
Free pupae floating in sea 
water 2 weeks. First-gen- 
eration pupae. 
Sept. 15 
..do 
Sept. 17 
..do 
Sept. 29 
Sept. 15 
..do 
..do 
..do 
..do 
Sept. 24 
Oct. 4 
Oct. 3 
Sept. 27 
'Aug. 6 
..do 
..do 
..do 
Aug. 3 
July 26 
Aug. 5 
..do 
..do 
..do 
June 1 
..do 
..do 
..do 
Aug. 7 
Aug. 
Aug. 
Aug. 
Sept. 
Sept. 
Sept. 
Sept, 
Oct. 
Sept. 
Sept. 
Sept. 
Sept. 
Sept. 
Sept. 
Oct. 
Oct. 
Sept. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
Aug. 
June 
June 
June 
June 
Days 
Aug. 21 
120 
72 
120 
72 
72 
120 
72 
168 
336 
67 
89 
24 
48 
72 
96 
336 
Larvae left stalks within 1 
hour and came to top of 
submerged container. 
Surviving larvae normal; 
not observed for pupa- 
tion. 
Larvae (A) to (D) left 
stalks within 1 hour. 
Surviving larvae dead 2 
days later. 11 larvae (E) 
dead in burrows. Sur- 
viving larvae alive Oct. 7. 
Larvae in (A) alive Nov. 30. 
(B) and (C) dead 3 days 
later. (D) to (F) alive 
Nov. 30. 
Surviving larvae strong and 
vigorous. Not observed 
for pupation. 
6 males and 3 females 
emerged. 
4 males and 2 females 
emerged. 
2 males and 4 females 
emerged. 
1 female emerged. 
3 males and 5 females 
emerged. 
3 males and 3 females 
emerged. 
1 male emerged. 
12 males emerged. All 
emergence in first 7 days. 
According to the data in Table 42 the larvae of the second or over- 
wintering generation proved to be much more resistant to drowning 
during their period of inactivity in the late fall, winter, and early 
spring than the first-generation larvae during summer or the second- 
generation larvae during early fall. Some of the larvae which sur- 
vived prolonged exposure to water in either floating or submerged 
plant material eventually pupated and emerged as adults. Very 
little difference was noted between the comparative effects of fresh 
or sea water upon the larvae and pupae. 
When infested cornstalks were submerged in water for 28 days 
during the winter, nearly 80 per cent of the overwintering larvae 
contained therein survived and many of such larvae eventually 
pupated and emerged as moths. Less than 2 per cent of the larvae 
survived for 43 days, however, when they were submerged under 
similar conditions a little later in the season. None of these pupated, 
although they lived for a maximum of 41 days after being taken 
