BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 
21 
INVESTIGATIONS OF INSECTS AFFECTING MAN AND ANIMALS 
INSECTICIDES DEVELOPED AT ORLANDO ADOPTED BY ARMED FORCES 
Three research projects undertaken at Orlando, Fla., on funds allo- 
cated by the Office of Scientific Research and Development sought to 
develop a satisfactory lousicide, an effective insect repellent against 
mosquitoes and other biting insects, and larvicides for malaria-carry- 
ing mosquitoes. By the middle of May 1943 the insecticide known as 
DDT was recommended for control of lice attacking man, and within 
a year it had proved its worth among troops and civilians in North 
Africa and Italy, especially in the control of a typhus epidemic in 
the Naples area. A mixture of three insect repellents was recom- 
mended during the year, and is in use by our military forces and their 
allies in different foreign lands. A new mosquito larvicide devel- 
oped at Orlando is being used successfully by our armed forces. 
NEW SPRAYS FOR CONTROL OF TICKS AFFECTING MAN 
For killing ticks about the premises of camps, playgrounds, parks, 
kennels, and residences, a spray containing 5 percent of DDT was 
found to be very effective. An emulsion of this material caused no 
injury to the vegetation, and when applied at the rate of 1 pound of 
DDT per acre it gave control of the ticks for about 6 weeks. 
For use about kennels and other locations where some temporary 
burning of foliage is not objectionable, a water spray containing 0.05 
percent of nicotine and 1.5 percent of sodium fluoride applied at the 
rate of 75 gallons per acre killed all stages of Ixodes ricinus scapu- 
laris (Say) and Dermacentor variabilis (Say). 
MOTHPROOFED FABRICS WITHSTAND LAUNDERING AND DRY CLEANING 
The effect of laundering or dry cleaning on fabrics previously treated 
with mothproofing agents has been studied. Fabrics treated with 
such agents as Mitin SS concentrate (a sodium salt of tetrachloro- 
diphenyl ether phenylurea monosulfonic acid), Eulan CN (penta- 
chlorotriphenylmethane sulfonic acid), and aqueous solutions contain- 
ing sodium fluosilicate were washed in soap and water, or dry-cleaned 
from one to ten times, and then subjected to attacks of the black carpet 
beetle. The results indicated that moth resistance may be given by 
the manufacturers of suitings, overcoat materials, blankets, and other 
woolen fabrics. These tests have demonstrated also the practicabil- 
ity of treating woolens in the home with moth-resistant sprays. 
NEW TREATMENTS SUCCESSFUL AGAINST SCREWWORMS AND FLEECE WORMS 
In limited field tests a new smear formula, known as P-55, af- 
forded good protection in wounds of animals from infestations by 
screwworm flies, but it was slightly less efficient than Smear G2, which 
is now in use. Since the new smear contains ingredients that are 
not critically needed for war purposes, it seems promising as a sub- 
stitute for Smear G2. Wounds of animals infested with screwworms 
healed as promptly after treatment with P-55 as those treated with 
Smear 62, but further tests of this kind are needed under ranch 
conditions. 
