-42- 
per 100 cc. and gives a kill of .50 to 60 percent by the Peet-Grady method. 
High-kill sprays were prepared in accordance with formulas published in 
conjunction with an invitation for bids from the insecticide industry. These 
samples were prepared in accordance with specifications N. Y. G. D. No. 334-3, 
November 20, 1935. Under Section V", No. 2, there were set forth specifications 
for three different combination sprays as follows: 
1. Not less than 0,3 percent of pyrethrins and 0.1 percent of 
rotenone. Derris extractives were permissive if the insecti- 
cide thereby contained not less than 0.1 percent of rotenone. 
2. Not less than 0.3 percent of pyrethrins and aliphatic thio- 
cyanates corresponding to a content of not less than 0.78 
percent of thiocyanoacetic acid (approximately 2.5 percent 
Lethane.) 
3. Aliphatic thiocyanates corresponding to a content of not less 
than 2.34 percent of thiocyanoacetic acid (approximately 7.5 
percent Lethane) plus 0.1 percent of rotenone. Derris extrac- 
tives were permissive If the insecticide thereby contained 
not less than 0.1 percent of rotenone. 
These sprays all gave better then 90-percent kill of houseflies, which 
places them in the class of sprays containing 400 mg. of pyrethrins per 100 
cc. Rotenone was added as a 1 gm. per 100 cc. solution in camphor-oil sassa- 
frassy. 
The Dow Chemical Company (77) in 1937 announced that it had prepared 
be ta-(p-tertiary-butyl-nhenoxy) ethanol, called Fly Toxic K-58. A 3-percent 
solution of this in oil gave a knock-down of 91 percent in 10 minutes and a 
kill of 45.5 percent in 48 hours by the Peet-Grady method. Mien 0.075 per- 
cent of rotenone is added to this the knock-dOTWi is raised to 99 percent and 
the mortality in 72 hours to 92.2 percent. Para tertiary butyl phenoxy ethanol 
is stated to be an excellent solvent for rotenone. Solutions in the base oil 
show no tendency for the rotenone to crystallize. This compound is also a 
stabilizer for rotenone. 
Simanton ( 252 ) in United States Patent 2,089,766 issued in 1937, claims 
an improved insecticide comprising in stable admixture a petroleum fraction, 
a substance chosen from the class consisting of ethylene glycol monethyl ether 
acetate and diethylene glycol monoethyl ether acetate, pyrethrins, and at least 
one of the active toxic ingredients of derris and cube. Among the solvents 
that have been employed as blending agents in combination with -oetroleum 
naphthas are: Ethylene dichloride, carbon tetrachloride, acetone, camrhor 
-sassafras oil, benzol, and chloroform. These solvents all objectionable for 
a variety of reasons, chief of which is that their odor is distinctly disagree- 
able. Ethylene glycol monoethyl ether acetate and diethylene glycol monoet 
ether acetate are each completely miscible with the petroleum fractions known 
as naphthas, and are also miscible to a more limited extent with higher 
-boiling petroleum fractions. 
