LIFE HISTORY 15 



gots. There had been considerable rain and the piles 

 were damp throughout. At one place there was a layer 

 of six or eight inches of soggy barley over the ground, 

 which was simply crawling with larvae. After six days 

 of continued dry weather, however, they had practically 

 all disappeared. 



An interesting experiment was made. One pound 

 of material from each of the breeding places was taken 

 to the laboratory and kept in screen-covered glass jars 

 for ten days, with the following result: 



Stable manure o adult flies issued 



Farm barn, horse end .... 77 



Farm barn, mixed 19 



Farm barn, cow end I 



Piggery manure pile 361 



Spent hops 129 



Barley malt 539 



fly 

 flies 



These results as recorded are very interesting and 

 are probably in the main correct, although Doctor Or- 

 ton states that the identification of species was by no 

 means thorough and the determination of the house 

 fly was made simply by observation of its size and gen- 

 eral appearance and the characters of the mouth parts. 

 It is possible that the stable fly (Muscina stabulans) 

 may have formed a portion at least of the flies bred 

 from the spent hops and the barley malt. 



There is a statement in Taschenberg's Praktische 

 Insektenkunde to the effect that the female house fly 

 lays its eggs not only upon spoiled and moist food- 

 stuffs, decaying meat, meat broth, cut melons, dead 

 animals, manure pits, manure heaps, but even in cus- 



