72 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Yol. 11 
greenhouse under similar temperature and light conditions, with the 
unfractionated oils, the different fraction of these oils, and the oils 
and fractions emulsified with soap and applied at various strengths. 
These oils were all emulsified using the Riley-Hubbard formula with 
ivory soap as the emulsifier. 
Results of spraying with the pure oils and emulsions of these oils 
are given in Table II. From these data it is evident that different 
Table II 
Name of Oil 
Applied 
Unfrac¬ 
tionated 
First 
Fraction 
Second 
Fraction 
Third 
Fraction 
A 
Pure 
4(2) 
5(4) 
4(3) 
4(1) 
A 
25% 
1(2) 
1(2) 
1(3) 
2(3) 
A 
10% 
A 
5% 
A 
3% 
B 
Pure 
4(6) 
4(5) 
5(4) 
5(5) 
B 
25% 
4 
4 
4 
4 
B 
10% 
3 
3 
4 
4 
B 
5% 
2 
2 
3 
4 
B 
3% 
3 
2 
3 
3 
C 
Pure 
5(5) 
5(6) 
6(5) 
6(3) 
C 
25% 
4(3) 
3(2) 
4(2) 
5(3) 
c 
10% 
3 
3 
4 
4 
c 
5% 
2 
2 
3 
3 
c 
3% 
3 
2 
3 
3 
D 
Pure 
5(4) 
5(5) 
6(4) 
4(3) 
D 
25% 
4 
3 
4 
4 
D 
10% 
4 
3 
4 
4 
D 
5% 
2 
2 
3 
4 
D 
3% 
2 
2 
2 
4 
E 
Pure 
5(2) 
6 
5 
3 
E 
25% 
2 
2 
2 
3 
E 
10% 
2 
2 
2 
1 
E 
5% 
2 
1 
2 
2 
E 
3% 
1 
1 
1 
1 
A 
5% diluted 
with hard 
H 2 0 
2 
3 
3 
2 
D 
5% diluted 
3 
3 
4 
4 
with hard 
H 2 0 
1—Uninjured. 2—Very slightly injured. 3—Slightly injured. 4—Injured. 5—Seriously injured. 6—Dead. 
Figures in parenthesis are the results of preliminary experiments carried out under varying conditions of light and 
temperature and illustrate how results may vary with varying conditions. 
brands of kerosene differ in their toxicity to plants, and further that 
there is a difference in the action on plants of the various fractions of 
the same brand. In using the pure oil it may be noted that the lowest 
fraction in general injured the plants less than the second fraction, 
but the second fraction produced as a rule greater injury than the 
third fraction. In the experiments it was noted that the first fraction, 
containing the oils with low boiling points, penetrated the leaves very 
quickly and the injury was noted - very much sooner than with the 
