The addition of pyrethrins or N-isobutylundecenamide failed to 
increase the repellent time of Indalone, ethyl hexanediol, or ethylene 
glycol ether of pinene. In most tests mixtures of the better repellents 
were more effective than the standard ethyl hexanediol. 
The addition of thickeners failed to increase the protection time of 
repellents, but generally powder-base creams to which thickeners had 
been added were more effective than the liquid repellents. Likewise, 
repellents formulated with a vanishing or cold cream were not 
effective. 
The repellent times were much longer with the mountain Aedes, 
Culiseta, and Mansonia than with the salt-marsh Aedes, but this may 
have been due to the low biting rates prevailing during the tests. 
Literature Cited 
(1) Morton, F. A., Travis, B. V., and Linduska, J. P. 
1947, Evaluation of materials as mosquito repellents. Part V. 
In Results of screening tests with materials evaluated 
as insecticides, miticides, and repellents at the Orlando, 
Fla., laboratory April 1942 to April 1947. U.S. Bur. 
Ent. and Plant Quar. E-733, pp. 10-11. 
(2) Smith, Carroll N., Cole, M. M., Lloyd, George W., and Selhime, Allen. 
1952. Mosquito-repellent mixtures. Jour. Econ. Ent. 45: 805-809. 
(3) Travis, B. V., Morton, F. A., Jones, Howard A., and Robinson, J. H. 
1949. The more effective mosquito repellents tested at the 
Orlando, Fla., laboratory 1942-47. (Scientific Note) 
Jour. Econ. Ent. 42: 686-694. 
(4) and Smith, Carroll N. 
1951. Mosquito repellents selected for use on man. (Scientific 
Note) Jour. Econ. Ent. 44: 428-429. 
