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Show Flies Frequently Travel Over One Hundred Miles THE marking and release of 234,000 files by expert government entomologists in order that these scientists mipht study in detail pecu llarities In fly behavior which previously had never been investigated thoroughly is one of the most remarkable undertakings and accomplishments accomplish-ments of recent years so far as "bugologists" are concerned. Federal representative? of the National Na-tional Bureau of Entomology have officiated as modern fly cops and insect detectives In these novel experiments, whose objects have been '.0 determine how alous species of economic Insects In-sects were distributed and how knowledge concerning con-cerning the Intimate daily doings of the winged pests could be used advantageously In developing efficacious control and eradication measures. The varieties of files which affect man and animaU aro largely distributed by natural dispersion through ordinary flight These unique fly tests wer-2 started in order that practical data might bo had which could be interpreted inter-preted in terms of the rpread of fly-borne diseases as well as to provide accurate data regarding regard-ing the proper location of dumps, incinerators, hog feeding stations and other favorable fly breeding grounds, so tbat the menace to surround lng towns, cities and rural districts would be avoided House flies may travel anywhere from one mile to fifty, or even 100 miles, in their iournevlngs about Observations made at the Rebecca Light Shoal off the coast of Florida show that flies occasionally migrate to that point from Cuba, a distance of 93 miles, while fly visitors from Key West, only forty-six miles away, are relatively commoL. The Federal fly investigations have been carried car-ried on chiefly in Northern Texas. The flies were captured by baiting laige conical fly traps with packing house products of strong odor. The traps were exposed In places which teemed with flies for anywhere from four to twenty-four hour" and then screened cylinders were placed around the fly traps, the covers of the traps were removed and then they were agitated until the flies were drien into the cylinders The free ends of the cylinders were then covered with cheesecloth and they were convened expeditiously to the point of liberation, where the cylinders, one at a time, were slipped Into a special canvas bag ontalning one or two ounces of finely powdered red chalk or paint pigment, which was thoroughly sprinkled over the capthe flies so as to mark them definitely definite-ly for future Identification. The flies were then liberated. Yellow chalk and rosallc acid were not satisfactory for marking tho flies, red chain and red pigment being tho best materials for this purpose. The flies flew away immediately after release from their paint box prisons, most of them speeding speed-ing with the wind or at right angles to its course, In order to ascertain tho distance of dissemination, a large number of conical traps IS inches in diameter were placed at varying distances in different directions from the points of liberation These traps were baited with strong-simdling by products which would attract the flies. The flies collected in these recovery traps were killed daily and counted, and the number of marked flies determined In case tho coloring matter could not be seen with the naked eye, microscopes were used which Invariably would favor the identification of all the experi mental flies In each lot. It is notable that over 64 per cent, of the total number of marked flits recovered were captured aga'n within twenty-four twenty-four hours after liberation Most of these flies previous to capture travelled at right angles ! a wind that was travelling at a velocity of from thirteen to twenty-four miles an hour. These experimental results show that for some une.v plained reason the flies of all species failed ro be recovered in the traps south of the points of liberation In numbers in pioportion to those recaptured re-captured in the traps placed in tbe other directions. direc-tions. These tests also showed that the files travel with a fair degree of speed, as they cover the first 1.000 feet from their place of release In a few minutes. The common house fly will cover from five to nine miles about two das Immediately Imme-diately after release. Tho tendency of the files was to travel In a westerly direction. 77 per cent, of them being recaptured in traps placed in that direction Tho stimuli which was largely responsible' foi the wide dispersion of the house flies were the desire for food and the desire for places where eggs would be deposited The fact that in their flignts the house flies passed many towns, fan. and other favorable places for feeding and breeding breed-ing Ind'cates that they possess maiked migratory habits Scientific American. |