PINK BOLLWORM OF COTTON IN MEXICO. 
41 
over, larvae removed from all seed and lint were placed in screened 
boxes and flowerpots and allowed to enter the soil. These were also 
buried flush with, the surface of the ground. A sample of the bolls 
used was examined at the time and found to contain an average of 
6.64 fourth-instar and 0.03 third-instar larvae per boll. The material 
was examined at different dates and the results are given in Table XXI. 
Table XXI. — The mortality among hibernating Pectinophora gossypiella larvx under 
different field conditions. 
Ex- 
Conditions of exposure. 
Examination. 
peri- 
ment 
No. 
Date. 
Live 
larvae. 
Dead 
larvae. 
Live 
pupae. 
Pupal 
skins. 
Remarks. 
557 
558a 
558C 
300 larvae removed 
from seed and lint 
and buried in wood- 
en box of soil in 
irrigated plot. 
50 larva? in flowerpot, 
same as 557. 
1919. 
June 11 
May 10 
June 10 
June 11 
June 11 
. 




2 
Several. 
3 












61 empty dirt cells 
around side of box. 
558b 
Same as 558a 
558D 
50 double seeds buried 
in flowerpot on irri- 
gated plot. 
Seed well rotted. 
560 
300 larvae removed 
from seed and lint 
and buried in wooden 
box of soil in nonirri- 
gated plot. 
50 larvse in flowerpot, 
same as 560. 
June 12 
12 
3 
2 
side of box. 
561A 
561b 
May 10 
June 11 
June 12 
28 

6 
1 
7 
1 

1 
1 

3 
Larvae in cocoons. 
561C 
50 double seeds in flow- 
erpot on nonirrigated 
plot. 
559A 
200 green and dry bolls 
buried 6 to 7 inches 
deep on irrigated 
plot. 
Mar. 10 (10 
bolls). 
Apr. 24 (10 
bolls). 
May 16 (50 



65 
48 






Bolls rotting badly. 
Very rotten and fallen 
to pieces. 
Fallen to pieces. 
200 green and dry bolls 
left on top of ground 
on irrigated plot. 
bolls). 
June 6 (130 
bolls). 
Mar. 10 (10 
bolls). 
Apr. 24 (10 
bolls). 
May 15 (50 
bolls). 
June 4 (116 
bolls). 

39 
20 


1 
10 

3 
Bolls so rotten difficult 
559b 
29 
36 
to pick from soil. 
Bolls in good condi- 
tion. 
Do. 
74 
51 
194 
344 
2 
6 
2 
18 
Some of bolls getting 
rotten, but those 
which had opened 
when experiment be- 
gan still in good con- 
dition. 
562a 
200 green and dry bolls 
buried in soil 6 to 7 
inches deep on non- 
irrigated plot. 
Mar. 11 (10 
bolls). 
Apr. 24 (10 
bolls). 
June 7 (180 
bolls). 
52 
13 


13 


2 


10 

Bolls badly rotted. 
Badly rotted and could 
not separate bolls. 
Thoroughly rotten. 
562b 
200 green and dry bolls 
left on top of ground 
on nonirrigated plot. 
Mar. 11 (10 
bolls). 
Apr. 24 (10 
bolls). 
May 15 (50 
bolls). 
June 7 (50 
bolls). 
July 25 (25 
bolls). 
Aug. 22 (80 
bolls). 
68 
54 
26 
28 




Bolls in very good con- 
dition. 
Do. 
83 
152 


137 
188 
100 


2 


6 
11 
7 

Do. 
Do. 
Do. 
Do. 
