Everyone was saying that bed linens and household effects of yellow-fever victims were dangerous. Even houses were burned down to get rid of the disease. Reed got piles of bed linen soiled with blood and discharges from dying men in the yellow fever ward. He put these bedclothes in a little house, especially built, and raised the temperature to over 90 . Into this house went three brave Americans who slept in this stench for 20 nights and then were quarantined in a tent to wait the attack of yellow fever. But they continued to be healthy.

Then Reed wondered if the men were susceptible to yellow fever. To test this he put three of his yellow fever mosquitoes on their arms and in a few days they had yellow fever.

They never found the microbe of yellow fever, but they did find that it was a virus too small to be seen.

The Gorgas Memorial Laboratory and the Health Department of the Panama Canal Zone, with help from the United States, continued the fight against yellow fever, which now exists only in small areas in Africa and Tropical America, where it exists in the jungle mosquitoes and monkeys. They have also continued the fight against malaria and other insect-borne diseases.

THE SECOND WORLD WAR increased the interest of the Armed Forces in entomology. The Army, in a cooperative arrangement with the Bureau of Entomology and Plant Quarantine, has done research work on insects affecting troops. During both World Wars attention was given to louse control and other insects that attack man,

The Army also worked on insect damage to food, clothing, and military supplies. The Navy Medical Corps has published much information on mosquitoes and their relation to disease. They have made a number of improvements in ways of applying insecticides from the air and in dispersing aerosols in aircraft.

Entomologists of the United States Public Health Service work on insect-borne diseases, such as malaria, yellow fever, plague, Rocky Mountain spotted fever, and several fly-borne diseases. They are also concerned with the biology of the insect involved in these diseases. The Hamilton, Mont., laboratory conducts work on ticks; the vaccine for Rocky Mountain spotted fever was discovered there. The Communicable Disease Center is concerned with plague, disease transmission by insects, ticks and mites, testing insecticides for their long lasting action and the development of equipment. Studies of malaria transmission and the effect of insecticides on man, are some of the activities of the National Institutes of Health.

The Public Health Service has been studying the malaria problem for many years. In 1945, using DDT, it started an eradication program with the help of various State Departments of Health in the Southern States.

Another Government agency that works on mosquito control is the Tennessee Valley Authority, which has prevented outbreaks of malaria along its hundreds of miles of reservoirs.

The Fish and Wildlife Service works with the Bureau of Entomology and Plant Quarantine, Tennessee Valley Authority, and the United States Public Health Service in studying the relation of mosquito control to wildlife, The Service also makes studies of insect enemies of game animals incidental to its routine work.

Entomology enters the work also of the Food and Agriculture Organization and the World Health Organization of the United Nations. They have a number of projects on insects in various parts of the world. The control of malaria-carrying mosquitoes, the protection of stored cereals against insects, and grasshopper control are problems vital to the welfare of many countries.

WORK ON several basic entomological problems is done in the Bureau of Plant Industry, Soils, and Agricultural Engineering of the Department of Agriculture breeding plants resistant to insects, special light-trapping devices, and equipment for applying insecticides.

The insecticide division of the Livestock Branch, Production and Marketing Administration, makes the use of insecticides safer and more effective by seeing that packages are properly labeled. This important work is done under the insecticide act of 1947, which requires all insecticide products to meet the claims of their labels.

The capstone of a large part of the entomological research is the insect collections in the United States National Museum. There specimens are studied and identified, for on proper identification rests any successful control action. Taxonomists of the Museum and the Bureau of Entomology and Plant Quarantine cooperate so closely that they function as one unit.

HELEN SOLLERS, an entomologist in the Bureau of Entomology and Plant Quarantine, is engaged in research on insects of medical and veterinary importance and prepares bibliographies on mosquitoes. She joined the Bureau in 1937.