350 
Journal of Agricultural Research voi. xxviii, No. 4 
EFFECT OF FUMIGATION UPON THE EGG 
Although Table III shows that 2 pounds of carbon disulphide per 1,000 cubic 
feet at 53° to 61° F. for 24 hours did not kill all the eggs of Bruchus obtectus, it 
shows that 3 pounds at 53°~to 58° F. prevented the hatching of any eggs, and Im¬ 
pounds at temperature only slightly higher killed all eggs in 48 hours. One 
and eight-tenths pounds of liquefied hydrocyanic acid per 1,000 cubic feet pre¬ 
vented the hatching of any eggs when exposed 24 hours at 62° to 70° F. 
Table III.— Effect of different kinds of fumigation for varying lengths of time on 
eggs of Bruchus obtectus 
Num¬ 
ber 
of 
eggs 
Date de¬ 
posited 
Date 
treated 
Material used 
Dos¬ 
age 
per 
1,000 
cubic 
feet 
Ex¬ 
po¬ 
sure 
Num¬ 
ber 
hatch¬ 
ed 
Num¬ 
ber 
failed 
to 
batch 
Temperature 
Humidity 
Maxi¬ 
mum 
Mini¬ 
mum 
Maxi¬ 
mum 
Mini¬ 
mum 
Lbs. 
Hrs. 
° F. 
° F. 
100 
Apr. 18 
Apr. 19 
CSa.. 
2 
24 
10 
90 
61 
53 
70 
66 
50 
_do_ 
_do_ 
_do_ 
2 
24 
0 
50 
61 
53 
70 
66 
100 
do .. _ 
( a ) 
89 
11 
76 
49 
68 
41 
50 
...do 
( a ) 
49 
1 
76 
49 
68 
41 
100 
Apr. 19 
Apr. 20 
CS 2 .-_ 
3 
24 
0 
100 
58 
53 
69 
66 
100 
_do... . 
(°) 
94 
6 
75 
49 
75 
45 
100 
Apr. 20 
Apr. 21 
CS 2 . 
1.5 
48 
0 
100 
68 
60 
64 
59 
50 
...do. 
...do_ 
.do.—_ 
1.5 
48 
0 
50 
68 
60 
64 
59 
50 
_do 
(«) 
46 
4 
85 
50 
70 
29 
50 
Apr. 22 
Apr. 23 
CS 2 __- 
1.5 
48 
0 
50 
60 
52 
68 
59 
50 
_do 
(°) 
41 
9 
69 
41 
68 
19 
100 
May 12 
May 13 
cs 2 _ 
3 
21 
0 
100 
68 
62 
73 
71 
100 
...do 
(“) 
83 
17 
81 
60 
82 
53 
50 
May 16 
May 17 
Liq. HCN_ 
1.8 
24 
0 
50 
70 
62 
70 
45 
50 
...do_ 
...do. 
_do.... 
1.8 
24 
0 
50 
70 
62 
70 
45 
50 
...do. 
(“) 
47 
3 
85 
51 
92 
44 
50 
June 7 
June 8 
CSj._ 
6 
21 
0 
50 
68 
64 
70 
66 
50 
...do. 
--do. 
_do. 
6 
21 
0 
50 
68 
64 
70 
66 
50 
do 
(°) 
46 
4 
87 
50 
83 
50 
50 
June 10 
June 11 
Liq. HCN. 
3.5 
48 
0 
50 
75 
62 
80 
58 
50 
...do_ 
...do. 
_do- 
3.5 
48 
0 
50 
75 
62 
80 
58 
50 
...do. 
...do_ 
.do. 
3.5 
48 
0 
50 
75 
62 
80 
58 
50 
...do. 
—do. 
_do-- 
3.5 
48 
0 
50 
75 
62 
80 
58 
50 
do 
(°) 
44 
6 
83 
64 
82 
54 
50 
do 
(°) 
46 
4 
83 
64 
82 
54 
50 
—do. 
(*) 
44 
6 
83 
64 
82 
54 
a Control. 
The most striking thing shown in Table IV is that at a temperature of 62° 
to 70° F. the viability of all the eggs of Bruchus quadrimaculatus was not de¬ 
stroyed by the use of 1.8 pounds of liquefied hydrocyanic acid per 1,000 cubic feet 
for 24 hours, although the same dosage (see Table III) killed all eggs of Bruchus 
obtectus. 
The eggs recorded in Tables III and IV were so arranged that there were eggs 
which had been deposited less than 24 hours, other eggs in every stage of devel¬ 
opment, and some just beginning to hatch. 
