400 
Journal of Agricultural Research 
Vol. XXVIII, No. 4 
Table VII.— Results , against the tent caterpillar and the Colorado potato beetle, 
of dusting wild-cherry foliage and tomato plants with organic compounds on 
which war gases had been adsorbed 
TENT CATERPILLAR ON WILD-CHERRY FOLIAGE 
Dusts 
W ar gas 
Number of insects 
First day 
Nun 
>> 
03 
a 
o 
o 
GO 
! (-> 
Third day ® 
0* 
Fourth day § 
_ Cl 
Fifth day 
I 
| Per cent killed 
Feeding 
Foliage 
injury 
Per 
cent 
Silica gel. . 
Phosgene. 
3.0 
20 
0 
0 
0 
0 
0 
Heavy_ 
None. 
Do.. 
Chloropicrin.__ 
20.0 
20 
0 
0 
0 
0 
0 
...do.:_ 
Severe. 
Do. .___ 
C hloracetophenone._ _. 
12.5 
20 
0 
0 
0 
0 
0 
...do. 
Slight. 
Do.. 
Arsenious oxid_ 
5.0 
20 
0 
12 
0 
3 
75 
Slight. 
Severe. 
Charcoal.. 
Phosgene.. 
25.0 
20 
0 
0 
0 
0 
0 
Heavy_ 
Do. 
Do.. 
Chloropicrin.. .. 
35.0 
20 
0 
0 
0 
0 
0 
_do_ 
None. 
Do.. 
C hloracetophenone_ 
11.0 
20 
0 
0 
0 
0 
0 
...do. 
Do. 
Do_ 
Arsenious oxid_ 
9.0 
20 
0 
11 
2 
4 
85 
Slight. 
Severe. 
Control... 
20 
0 
0 
0 
0 
j 
.... 
0 
Heavy.... 
COLORADO POTATO BEETLE ON TOMATO PLANTS 
Per 
cent 
Silica gel_ 
Phosgene__ 
3.0 
20 
0 
0 
0 
0 
0 
Heavy.. 
None. 
Do.. 
Chloropicrin_ 
20.0 
20 
0 
o 
0 
0 
0 
Medium.. 
Do. 
Do...... 
C hloracetophenone_ 
12.5 
20 
0 
0 
0 
0 
0 
Heavy_ 
Do. 
Do_ 
Arsenious oxid_ 
5.0 
20 
0 
0 
None_ 
Severe. 
Charcoal.. 
Phosgene__ 
25.0 
20 
0 
0 
.. do. 
Do. 
Do_ 
Chloropicrin.. __ 
35.0 
20 
0 
o 
0 
0 
0 
Heavy.... 
None. 
Do...._ 
C hloracetophenone_ 
11.0 
20 
0 
0 
0 
0 
0 
...do. 
Do. 
Do___ 
Arsenious oxid_ . 
9.0 
20 
0 
0 
None _ 
Severe. 
Control.. 
20 
0 
0 
0 
0 
.... 
0 
Heavy_ 
None. 
ALKALOIDS 
The alkaloids listed in Table VIII were ineffective. The unexpected resistance 
of insects to these alkaloids has also been observed by Crozier 4 and by Richardson 
and Smith. 5 The reason for the experiments with alkaloids was detailed in 
another paper by Moore. 6 
Table VIII.— Results, against the Japanese beetle, of spraying smartweed plants 
with alkaloids 
Compound 
Rate of application 
(pounds per 50 gal¬ 
lons water) 
Number of insects 
First day 
Second day 
z; 
Third day | 
o' 
jr deac 
>» 
c3 
S 3 
u 
o 
PR 
Fifth day j 
Sixth day 
[ Per cent killed 
Feeding 
Foliage 
injury 
Atropine sulphate_ 
0.001 
20 
0 
0 
0 
0 
0 
0 
Heavy 
None 
Strychnine sulphate_ 
.002 
20 
0 
0 
0 
0 
0 
0 
...do_ 
Do. 
Morphine sulphate_ 
.005 
20 
0 
0 
0 
0 
0 
_do_ 
Do. 
Do_ 
.005 
20 
2 
2 
0 
0 
0 
20 
do 
Do. 
Veratrin.... 
.005 
20 
0 
0 
0 
1 
0 
5 
do 
Do. 
Control__ 
20 
0 
0 
0 
0 
0 
0 
.do. 
Do. 
4 Crozier, W. J. reversal of inhibition by atropine, in caterpillars. Biol. Bui. 43:239-245. 
1922. 
5 Richardson, C. H., and Smith, C. R. studies on contact insecticides. U. S. Dept. Agr. Bui. 
1169, 15 p. 1923. 
6 Moore, W. the reaction of the Japanese beetle to arsenical spray deposits. Jour. Econ. 
Eat. 15: 67-70. 1922. 
