ENTOMOLOGY

454 SAN"iTARY ENTOMOLOGYskipper fly Piophila casei Linnaeus. Hide and ham beetles, mostly of thefamily Dermestidae, are of local importance, especially as destructive tohides. The three common cockroaches are to be found, especially theAmerican roach and the Croton ~ug.Associated with all the larger packing houses are large stock yards,horse and mule barns, rendering plants, and thickly populated districts,all of which are prolific insect breeding places. These furnish part oftheir millions of flies, with those produced on the premises of the packingplants themselves, to constantly attack th~ fresh products of the estab·lishments. Sanitation throughout the establishments and premises undergovernment inspection, and in railway cars and other vehicleS' used intransporting meats, is rigidly enforced, but government inspectors haveno jurisdiction over sanitary matters beyond that, no matter how badthe existing conditions may be.With efficient city health departments a great deal can be done cooperativelywith the sanitary force of the packing establishments, but this isnot always possible and as a res.ult the production of myriads of fliesgoes on constantly in the immediate neighborhood of the plants and thetask of protecting meat products and controlling flies at packing housesbecomes proportionately more perplexing. In our Southern States thisis an aU-year-round work, due to the fact that our winters are rarelysufficiently severe to cause the death of immature stages and during warmdays numerous adults emerge and seek food ·and protection in the con-. '·stantly heated tankage and blood-drying rooms or other favorabledepartments. Here they also find large stores of excellent breedingmaterial and can develop to maturity in a comparatively short time duringthe winter months. The breeding of blow flies in large accumulations oftankage and blood in drying rooms, as it is found in many packing houses,may take place during the winter even in the more northern latitudesas there are many species of blow flies that are quite resistant to coldand have the advantage of many warm, protected places during severewinter. .That flies are carriers of many different diseases is well known. Thegerm-laden flies can easily contaminate many diff~rent cured meatproducts which are sometimes consumed without being cooked, or contaminatefresh meat products with putrefactive, non-pathogenic and path·ogenic bacteria, in this way hastening decomposition, and rendering themeat unfit for food. There is also loss of much meat that is "blown"with eggs or damaged by skipper fly Iarvre.Next in importance to flies in meat paeking establishments are cockroaches.Although they arc not as numerous as flies, they are presentin almost all establishments just as they are more or less plentiful indwelling houses. The damage done by cockroaches is due not so much