In 1944 Mr. Stage conducted similar tests in Alaska against several 
species of Aedes (table 13). At Nome powder pastes containing dimethyl 
phthalate were the most effective repellents against a mixed population 
of nearcticus and riparius D. and K., and mixture 6-2-2 was superior 
to any one of its ingredients. In tests near Anchorage with flavescens 
(Mull.) and species of the stimulans group,he found ethyl hexanediol and 
dimethyl phthalate to be of equal effectiveness and mixture 6-2-2 to be 
superior to any one of its ingredients. Powder pastes with dimethyl 
phthalate and mixture 1-1-1 were much superior to the liquid repellents. 
In tests near Fairbanks with four repellent creams against mixed popula- 
tions of cinereus and excrucians (Wlkr.), the one containing N-sec- 
butylphthalimide was the most effective. ahaa 
C. R. Twinn, of the Canadian Department of Agriculture, made a 
number of field tests against woodland Aedes in Canada with the four 
standard repellents. He reported the following repellent times (in 
minutes): Dimethyl phthalate 267, ethyl hexanediol 329, Indalone 106, 
mixture 6-2-2 360. 
Miscellaneous Species 
In response to a request from the Bureau’s Division of Plant Disease 
Control, one of the more promising materials, 2-phenylcyclohexanol, 
was sent to its field employees in 20 States, who compared it with the 
repellent they were using, which was presumed to contain dimethyl 
phthalate. When all the reports were summarized, 571 tests with 
2-phenylcyclohexanol gave an average repellent time of 114 minutes 
and 475 tests with the standard gave 106 minutes. Both these figures 
are lower than those obtained by the research group at Orlando, Fla., 
but the data seem to be in line with what might be expected from 
practical tests. 
Summary 
From 1942 to 1946 a large number of compounds and formulations 
were tested in the field against several species of culicine mosquitoes 
in an effort to find some that would protect troops from mosquito bites 
longer than the standard repellents. 
Against Aedes taeniorhynchus (Wied.) the best materials were 
2-(x-chloro-y-ethylphenyl)ethanol; N-butyl-4-cyclohexene-1,2- 
dicarboximide; N-isopentylacetanilide; 1,2, 3,4-tetrahydro-2-naphthol; 
2,5,7-trimethyl-3-octyne-2,5-diol; and the propyl ester of N,N-diethyl- 
Succinamic acid. Only the last one has been cleared in pharmacological 
tests for use on the skin. 
Tests with the four standard repellents--dimethyl phthalate, ethyl 
hexanediol, Indalone, and mixture 6-2-2--showed that the mixture gave 
the most consistent results and Indalone the least consistent. 
