PINK BOLLWORM OF COTTON IN MEXICO. 
49 
tailed account of the fumigations that were made with carbon 
disulphid. 
Table XXV. — Preliminary fumigation experiments with carbon disulphid for P. gos- 
sypiella in cotton seed. 
Dosage. 
Experi- 
ment 
No. 
Length 
of ex- 
posure. 
Pounds. 
Cubic 
feet. 
Hours. 
1 
1 
102 
90 
2 
1 
161 
48 
3 
1 
289 
48 
4 
1 
161 
23 
5 
1 
161 
23 
6 
1 
161 
48 
7 
1 
103 
48 
8 
1 
124 
48 
9 
1 
82 
48 
HO 
1 
54 
24 
11 
1 
80 
42 
13 
1 
100 
1 week . 
19 
1 
100 
Hours. 
48 
20 
1 
80 
48 
21 
1 
80 
48 
22 
1 
80 
48 
23 
1 
80 
24 
26 
1 
80 
12 
27 
1 
80 
15 
29 
1 
85 
24 
30 
1 
85 
24 
31 
32 
1 
1 
90 
90 
24 
24 
How seed was 
stored. 
Location of larvae. 
Per 
cent 
killed 
in each 
loca- 
tion. 
Total 
per 
cent 
killed. 
In sacks.. 
do.... 
....do.... 
....do.... 
....do.... 
In bulk . . 
....do.... 
....do.... 
....do.... 
do.... 
In bags. 
In bulk 6 feet deep. 
In bulk 5 feet deep 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
("Top sack 
\Bottom sack 
(Top sack 
\Bottom sack 
(Top sack 
(Bottom sack 
(Top sack 
\Bottom sack 
JTopsack 
(Bottom sack 
(2^ feet deep 
\4^ feet deep 
f2|feet deep 
\4^feet deep 
f2|feet deep 
\4Jfeet deep..- 
(2|-feet deep 
\4§feet deep 
(2|-feet deep 
(4§feet deep 
fOntop 
< In center 
|On bottom 
On top 
2 feet deep 
4 feet deep 
6 feet deep 
{18 inches from to;: 
Middle 
Bottom 
/Middle 
IBottom 
{Middle 
IBottom 
/Middle 
IBottom 
Bottom 
/Middle 
\Bottom 
(Middle 
(Bottom 
(Middle 
(Bottom 
(Middle 
(Bottom 
Bottom 
....do 
100 
100 
100 
100 


12 
16 
60 
26 
100 
20 
100 
45 
31 

100 
75 
100 
80 
100 
100 
100 
100 
100 
84 
82 
100 
97.5 
75 
100 
100 
100 
100 
100 
100 
100 
100 
90 
85 
80 
100 
100 
100 
100 
85 
60 
100 
100 

14 
43 
60 
72 
90 
100 
91 
100 
100 
100 
100 
95 
•82.5 
100 
100 
J In Experiment No. 10 the larvae were placed in glass tubes, which were closed with cork stoppers, 
making them approximately air tight. 
In experiments 20, 21, and 22 all larvae were killed with 1 pound 
of disulphid to 80 cubic feet in 48 hours. In order to shorten the 
time, experiments 23, 26, and 27 were made, and all the larvae were 
not killed. All of the disulphid had not evaporated at the end of 
12 and 15 hours in experiments 26 and 27, but it had evaporated in 
experiment 23 in 24 hours, and all the larvae were killed, showing 
that 24 hours are necessary to evaporate and to secure maximum 
penetration of 1 pound of disulphid in 80 cubic feet. This was in 
