Pine Bluff daily graphic., 1915-01-12
OF FLIES
 SUBJECT OF STUDY
Experiments Show Pests Travel Great Distances in
 Search of Food.

One of the problems that has arisen in connection with the part played by insects as carriers of disease con cerns the distance which they may be able to travel from one locality 10 another This has frequently been considered in this country in connec- tion with mosquitoes which are re- sponsibe for the prevalence of ma laria With their breeding p!a ces known, it has become desirable i,' some cases to ascertain what the range of their activities might be in respect to the territory which can b. covered by insects. It has been learned that mosquitoes which in habit salt marshes near the seacoast may be found inland at distance as great as three miles,
 Far less appears to be known with regard to the migrations of the com- mon house-fly, an insect charged with responsibility for typhoid fever ant other infectioCs diseases. A series of studies conducted in Cambridge England, on the range of the flight of flies of this species has been made the subject of report to the loca' government board on public health and medical subjects. Upward of 23,- 900 flies were liberated, under vari- ous meterologic conditions, from the medical buildings at Cambridge. Of these insects, colored foE identifica- ton. 191 we:e :eccv'Icd The re- suits showed that house fli"s tend 10 travel either against or across tho wnl The actual direction followed may pc determined either directly anl cy the action of the wind, or indirect ly owing to the flies being attracted by odors from food. A point in favor of this supposition is the nature of the station at which flies were re- covered after they had travelled any distance. These comprised butchers shop, public houses and restaurant all of which gave off odors that are notoriously attractive to flies. The chief conditions favoring the dis persal of flies are fine weather and a warm temperature. The nature of the locality is another considerable factor. because in towns flies do not travel as far as in open country probably due to the food and shelter afforded by the houses. With regard to the altitude of the point of libera- tion, flies set free from the roo1 tended 10 disperse slightly better thar those liberated from the ground but the differences are not very con- siderable. It has been observed, witt regard to the vertical flight of the house-fly, that it may mount almos directly upward to a height of 4; feet or more. The time of day ap pears to influence the dispersal of tht insects, as, apparently, when set fre' in the afternoon they do not scatte so we'll as when liberated in tn morning.
 The maximum flight observed il the thickly housed localities in Cam bridge was about a quarter of mile tance was across open fenland. ; flight of 770 yards was noted II experiments conducted in Cook coun ty, Illinois, by s. A. Forbes. file were trapped and, after being spraye, with chemical solution for recosni tion, were liberated from hospita in that district. They too were recov cred at distances ranging up to quarter of mile from the point o
 liberation. The distance flies mn
 travel to reach dwellings is controllei
 by circumstances. Almost any reas
 enable distance may be covered b'
 the fly under compulsion to rcacl food and shelter.