LIFE HISTORY 11 



found breeding by Mr. Newstead in certain temporary 

 breeding places, such as collections of fermenting vege- 

 table refuse, accumulations of manure at the wharves 

 and in bedding in poultry pens. Mr. F. V. Theobald 

 states that swarms of flies are reported to breed in the 

 huge masses of dust-bin refuse in certain London sub- 

 urbs. It does not appear to be certain, however, that 

 these are Musca domestica. 



In India, according to the observations of Surgeon 

 Major F. Smith, of the Royal Army Medical Corps, 

 horse manure is the most abundant breeding place for the 

 house fly around military stations. He also reared this 

 fly from cow dung in company with Musca entaniata. 



DeGeer states that the larvae of this species live in 

 dung, but only in that which is warm and moist, or, 

 stated better, which is in a condition of perfect fermen- 

 tation. The importance of the factor of fermentation 

 has already been referred to in the account of Mr. 

 Newstead's observations and is insisted upon by Dr. 

 C. Gordon Hewitt in Part II of his important paper 

 on the Structure, Development and Bionomics of the 

 House Fly. He points out that Keller, writing of this 

 fly in 1790, reared the larvae of the typhoid fly in de- 

 caying grain, where no doubt fermentation was taking 

 place; also in small portions of meat, slices of melon, 

 and in old broth. Doctor Hewitt also found that horse 

 manure is preferred to all other substances by the fe- 

 male flies for egg-laying. He also found that the lar- 

 vae will feed upon paper and textile fabrics, such as 

 woolen and cotton garments and sacking which were 



