MOSQUITO CONTROL TESTS — STAGE 



351 



different repellents gave protection for different lengths of time on 

 different hosts, but in general the effective period was shortest for 

 Indalone and longest for the three-wa}' mixture 6 parts dimethyl 

 phthalate, 2 parts Indalone, and 2 parts E-612. The repellents were 

 applied carefully and thoroughly, and after each application we 

 washed our hands with acetone to avoid contaminating any one repel- 

 lent with any other. We would test but one repellent on any one arm 

 or leg during the course of any one day. On any day when the biting 

 rate of mosquitoes was abnormally low because of unfavorable weather, 

 we interrupted the test repellents and instead tested some tents and 

 sleeping bags Moore had designed. From time to time we used jungle 

 boots and jungle hammocks. The hammocks were warm and com- 

 fortable, and after we got inside we were well protected against mos- 

 quito bites — that is, unless an arm or leg came into contact with the 

 netting. Wearing jungle boots in that cold and saturated moss-covered 

 muskeg was another story, and none of us volunteered to test them a 

 second time. 



Table 1. — Repellent test. Mosquitoes: ^ Aedes nearcticus, Aedes catapbjdla. 

 July 7, 194s, Churchill, Manitoba. Biting rate, 61 per minute 



1 Each host tested 4 repellents simultaneously, 1 on ench arm and each leg. 



' Plus sign signifies that test was terminated Kt the end of the time indicated because of rain. 



2 A mixture containing 6 parts dimethyl phthalate, 2 parts Indalone, 2 parts R-612. 



77748S — 48- 



-2G 



