-45- 
prepared by forming a -paste or heavy dispersion of pondered derris 
root in the ester therein 10 parts of the root were admixed v- ith 25 
parts "by weight of the ester. This mixture was then heated at 100° C. 
for 1 hour. The extract ras removed "by filtration, yielding in most 
cases extracts having straw-yellow to brown-red color. Four-percent 
solutions of each of the extracts ^ere then made using a deodorized 
kerosene solvent suitable for insecticide! tests end filtered when- 
ever necessary. The insecticidal effects of these solutions were 
then compared to that of similar concentrations of the esters alone 
by bio-assays, using houseflies under identical controlled conditions. 
The results of these tests are shown in the following table. 
Esters used as extractants 
Pure ester only | Ester and 
I extracted 
: . rotenone 
A. Derris root extractions 
Percent 
Mesityl oxide oxalate, ethyl ester 9 
Mesityl oxide oxalate, n-butyl ester 30 
Mesityl oxalate, iso-butyl ester 16 
Mesityl oxalate, sec-amyl ester 53 
Mesityl oxide oxalate, cyclohexyl ester 17 
Mesityl oxide oxalate, tetrahydrofurfuryl 
ester 
Acetalacetone exalate, n-butyl ester 
n-Butyralacetone oxalate, ethyl ester 
4 
80 
6 
45 
3-Methyl-3-pentene-2-one oxalate ethyl 
ester 
3-M eth yl-3-hept en e- 2- one- oxalate, ethyl 
ester 
Tetrahydroacetophenone oxalate, ethyl 
ester 
B. Tephrosia virginiana root extraction 
Mesityl oxide oxalate, n-butyl ester 30 
_C. Cube root extraction 
Mesityl oxide oxalate, n-butyl ester 30 
Percent 
100 
100 
100 
100 
100 
85 
100 
95 
85 
100 
98 
67 
62 
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STATE PLANT BOARD 
