454 SANITARY ENTOMOLOGY 



skipper fly Piophila casei Linnaeus. Hide and ham beetles, mostly of the 

 family Dermestidae, are of local importance, especially as destructive to 

 hides. The three common cockroaches are to be found, especially the 

 American roach and the Croton bug. 



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 of 

 their millions of flies, with those produced on the premises of the packing 

 plants themselves, to constantly attack the fresh products of the estab- 

 lishments. Sanitation throughout the establishments and premises under 

 government inspection, and in railway cars and other vehicles used in 

 transporting meats, is rigidly enforced, but government inspectors have 

 no jurisdiction over sanitary matters beyond that, no matter how bad 

 the existing conditions may be. 



With efficient city health departments a great deal can be done cooper- 

 atively with the sanitary force of the packing establishments, but this is 

 not always possible and as a result the production of myriads of flies 

 goes on constantly in the immediate neighborhood of the plants and the 

 task of protecting meat products and controlling flies at packing houses 

 becomes proportionately more perplexing. In our Southern States this 

 is an all-year-round work, due to the fact that our winters are rarely 

 sufficiently severe to cause the death of immature stages and during warm 

 days numerous adults emerge and seek food and protection in the con- 

 stantly heated tankage and blood-drying rooms or other favorable 

 departments. Here they also find large stores of excellent breeding 

 material and can develop to maturity in a comparatively short time during 

 the winter months. The breeding of blow flies in large accumulations of 

 tankage and blood in drying rooms, as it is found in many packing houses, 

 may take place during the winter even in the more northern latitudes 

 as there are many species of blow flies that are quite resistant to cold 

 and have the advantage of many warm, protected places during severe 

 winter. 



That flies are carriers of many difl'erent diseases is well known. The 

 germ-laden flies can easily contaminate many diff^erent cured meat 

 products which are sometimes consumed without being cooked, or con- 

 taminate fresh meat products with putrefactive, non-pathogenic and path- 

 ogenic bacteria, in this way hastening decomposition, and rendering the 

 meat unfit for food. There is also loss of much meat that is "blown" 

 with eggs or damaged by gkipper fly larvs. 



Next in importance to flies in meat packing establishments are cock- 

 roaches. Although they are not as numerous as flies, they are present 

 in almost all establishments just as they are more or less plentiful in 

 dwelling houses. The damage done by cockroaches is due not so much 



