ENTOMOLOGY

162 SANITARY ENTOMOLOGYbum or bury. Foreman and Graham-Smith have ably shown the valueof coal tar creosote oil as a deodorizer, preventive of decomposition, andBy destroyer in carCaSses. This subject is fully treated by Mr. Bishoppin the chapter on myiasis (Chapt~r XIII).Miscellaneous breeding placesFactory waste, rotting vegetable matter, the accumulation of debrisalong shore line!!, chicken yards, pig pens, alleys, streets which are notswept, gutters, etc., furnish fly-breeding places (see Chapter XI). Mr.Laake's able presentation Of packing-house problems in another lecturecovers that subject sufficiently (see Chapter XXXIII).PALLIATIVE MEASURESIn view of the fact that flies can come great distances, possibly evenover 50 miles as indicated by Ball at Rebecca Shoal, the sanitarian is notalways responsible for all the flies that visit the locality under his ju.risdiction.There is therefore always the necessity of taking measuresagainst the flies themselves, although this is entirely sec,?ndary to theprevention of breeding.Screening.-All foods must be protected from flies because many ofthe flies which visit foods lay eggs therein.· This is especially true ofmeats which are attacked by blow flies, and cheeses which are attackedby skippers. City markets should not expose meats for sale uncovered, asthe attraction to flies is too great. ' A well-screened house will have theleast trouble from flies. In army camps anywhere in the United Statesall sleeping quarters, kitchens, and mess halls should be well screenedagainst flies. All hotels throughout the country, especially in rural communities,should be required to screen all windows and doors.The fly situation around small country hotels is by far the mostrepulsive that can c,rdinarily be found in any community. Very little,if any, care is taken of the privies and the flies come directly from thereto the kitchen and dining rooms. .Screening of garbage cans has been mentioned and is an admirableprocedure. A screened enclosure around privies and latrines would assistin keeping flies away.Fly Traps.-Fly traps of many different designs have been devised.The most efficient is the cone and cylinder type devised by Bishopp (fig.35). The Hodge window trap is good. A small cone and cylinder trapmay be inserted in the lid of garbage cans (fig. 34). The principle of alldifferent traps is the attraction of the flies by a good bait, and thearrangement of the trap so that once there the fly can' not get away. At