August, ’23] simmons: house fly plague, American exp’d forces 
359 
Mr. C. T. Dodds, a man with entomological training, failed to indicate 
the stable as a source of flies. The men’s drinking water was supplied 
from two Lister bags, , care being taken to chlorinate it whenever fresh 
water was put in. Personal cleanliness was the rule in camp and no 
cases of pediculosis in 1918 were reported, except two or three cases 
prior to the installation of the shower baths. 
The men were careful about the disposal of excreta in the neighborhood 
of the camp. This was practically never deposited in the nearby 
woods, and during the period when open trench latrines were emplo}^ed 
the sandy nature of the soil made it possible to push a large amount into 
the trenches with one turn of the foot and this matter was observed 
conscientiously by the men. 
A small amount of fly breeding possibly occurred at the buckets where 
mess kits or dishes were washed, but was not observed in our inspections. 
Here the garbage receptacles sometimes were filled to overflowing, and 
w^ater splashed or leaking from the wash buckets kept the sand moist. 
The flies (principally Musca domestica L.) began to be numerous before 
the middle of June. By the last of the month they were very bad. 
It was found impossible with the limited amount of wire screening on 
hand to fly-proof the mess hall which had been built of green lumber. 
About the time the swarms of flies appeared the men were eating from 
dishes (instead of from mess kits) and helped themselves from cans 
placed on the tables before mess call. The flies simply swarmed over 
the food, and newspapers laid over the food dishes proved nearly useless 
as a protection. The non-commissioned officers’ mess was served in a 
small room next to the kitchen where the flies were particularly bad. 
Before the men sat down the food was covered with flies, especially the 
meat, gravy and bread. It was necessary to eat with one hand and 
to use the other to keep the flies away. Darkening the room had no 
effect and conical fly traps, placed by Mr. Dodds at the two windows, 
caught comparatively few. Between meals the only light entering the 
room came through these traps but the flies preferred to remain inside. 
Similar traps were placed over holes in the large latrine and great 
numbers of flies which probably matured in the pit below, were caught. 
It was out of the question to cover all the cracks left by the drying 
lumber or to construct the lids to prevent the passage of flies. Thousands 
of flies remained at rest on the rafters and roof boards, particularly in 
the evening, and an attempt was made in desperation to kill them with a 
blow torch. This treatment resulted in few deaths as the flies fell off 
with only their wings burned and crawled about, a worse nuisance than 
