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star pink bollworms at Presidio, Tex. Derris dust diluted with flour 
to 0.75 percent of rotenone killed 86.. 5 percent in 2-1/2 hours; cube 
dust of equal strength killed 100 percent in 2-1/2 hours. 
Sitotroga cersalella (Oliv.) the Angoumois grain moth 
Breakey and Miller (4-8) in 1935 reported the results of tests 
with rotenone as follows: 
Rotenone sprays were prepared from an extract of derris 
in pine oil, assaying 5 gm» of rotenone for each 100 cc. Emul- 
sions were made fr m this stock containing 1 part of rotenone, 
19 parts of pine oil, 5 parts of saponin, and 75 parts of water. 
Dilutions made from these emulsions gave the desired concen- 
trations of rotenone. An attempt was also made , to use rotenone 
as a colloidal suspension, preparing the suspensions from an 
extract of derris in acetone with the aid of a protective 
colloid, tannic acid. The results obtained from the use of 
trese suspensions confirmed, in general, those obtained from 
the use of the emulsions* However, since there appeared to 
be impurities present in the suspensions which might affect 
the behavior of the toxin, these results have not been used 
in preparing this paper. A concentration of 1 part of 
rotenone in 50*000 parts of the spray killed more than 95 
percent of the eggs. 
Smerinthus ocellatus (L.) 
Trappmann and Nitsche ( 417 ) in 1935 reported that rotenone 
sprays and dusts were not effective against fourth and last in- 
stors, respectively, of this species. Dosage was regulated to 
give a deposit of 0.18 mg. of rotenone per 500 cm. . 
Klinger ( 237 ) in 1936 reported that rotenone spray (0.18 mg. 
per 500 cm. 2) killed 5 percent in 6 days and rotenone dust 
(0.15 mg. per 415 cm. 2) killed none in 8 days. Derris dust killed 
60 percent in 4 days. These tests were made in the laboratory on 
fourth instars. Rotenone and ground derris root produced no 
symptoms of poisoning when applied to the body segments of larvae 
of this species. 
Geometridae 
Abraxas grossulariata (L.) 
DeBussy et al. ( 57 ) in 1936 reported that the magpie moth 
is sensitive to derris dust. 
Van der Laan ( 244 ) in 1936 reported that a plague of the 
currant canker^orm on gooseberry in the Netherlands was effectively 
controlled with derris. 
Alsophila pomet-:.ria (Parr.), the fall cankerworm 
Felt and Bromley (126) in 1937 reported the results of tests 
