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10'6 per cent, and 5'9 per cent, respectively, those in shady places 

 attracted 3'6 per cent, on excrement and 2"4: per cent, on animal matter. 

 It is therefore recommended that manure, etc., should be kept in shady 

 situations. Several species, including C. erythrocephala, C. vomitoritty 

 F. scalaris, L. caesar and M. stabulans, which visit both excrement 

 and animal matter, seldom enter houses and are thus of little importance 

 as carriers of disease in this country. They may however be very 

 important under war conditions. Pyrellia eriophthalma, Pseudopyrellia 

 cornicina, Morellia hortorum, Polietes lardaria and Scatophaga frequent 

 excrement, but seldom visit animal matter. Species belonging to the 

 genera Calliphora, Lucilia, Muscina, Sarcophaga, Hydrotaea, and 

 Polietes are seldom found in shady places, while Phormia groenlandica, 

 P. cornicma, M. hortorum and Ophyra leucostoma are entirely absent 

 from such situations. Small Anthomyidae however are abundant. 

 With regard to seasonal abundance, P. groenlandica appeared early in 

 June, was numerous in September, and disappeared at the end of 

 October. Lucilia spp. appeared in May, increased in numbers until 

 the beginning of September, then decreased rapidly. Isolated 

 individuals of P. eriophthalma occurred in February and March, and 

 larger numbers in May and June. Few specimens were then found 

 until October. P. cornicina occurred in small numbers between June 

 and September, and was abundant during October. The seasonal 

 distribution of the following species is also noted : — Pollenia rudis, 

 M. autumnalis, M. stabulans, M. hortorum, S. calcitrans, Sarcophaga spp., 

 Onesia cognata, Hydrotaea dentipes, P. lardaria, and 0. leucostoma. 

 Of the total number of flies visiting the traps, 16 per cent, were males, 

 while in the dark receptacles only 5 per cent, were males. In the cases 

 of C. erythrocephala, C. vomitoria and Lucilia, both males and females 

 visited excrement placed in the open only for the purpose of feeding, 

 while oviposition took place in excrement placed in dark receptacles. 

 Young specimens of Lucilia were attracted to human excrement for 

 food. Ripe fruit proved attractive to those species which visited 

 excrement and animal matter, but in this case males formed 38 per 

 cent, of the total number captured. Cultures made from fruit which had 

 been exposed to wasps and flies showed the presence of B. coli, thus 

 proving that fruit is liable to contamination by these insects. Only 

 10 specimens of M. domestica were captured in the traps, two being 

 found in the galvanised iron type placed in the open and baited with 

 animal matter and the remainder in the fruit trap. 



The larvae of some species, especially in the later stages, tend to 

 migrate, even though the food supply is abundant. Those of 

 H. dentipes, M. stabulans, Graphomyia maculata, Polietes albolineata, 

 Phaonia erratica and Azelia macquarti are predaceous on the larvae of 

 other species. Many species can develop in buried carcases, and when 

 mature, are able to reach the surface of tightly-packed earth, undergo 

 pupation, and emerge as adults. The burial of carcases has however 

 the effect of preventing the deposition on them of large numbers of 

 eggs. The baits used in the traps proved attractive to various species 

 of wasps, as did also animal carcases exposed in an open field. Blow- 

 flies feeding on the carcases were frequently captured by them, and as 

 their legs and mouth-parts must therefore become contaminated, it is 

 piobable that they disseminate pathogenic and putrefactive bacteria. 



