The House-fly as a Carrier of Disease 
147 
ff. With legs more or less yellowish; palpi 
yellow. Larvae in decaying vegetable 
substances, dung, etc. M. stabulans 
It is almost universally believed that the adults of Musca domestica 
hibernate, remaining dormant throughout the winter in attics, 
around chimneys, and in sheltered but cold situations. This belief 
•has been challenged by Skinner (1913), who maintains that all the 
adult flies die off during the fall and early winter and that the species 
is carried over in the pupal stage, and in no other way. The cluster- 
fly, Pollenia rudis, undoubtedly does hibernate in attics and similar 
108. The house or typhoid fly (Musca domestica ( 4 .x)). After Howard. 
situations and is often mistaken for the house-fly. In so far as 
concerns Musca domestica, the important question as to hibernation 
in the adult stage is an open one. Many observations by one of the 
writers (Johannsen) tend to confirm Dr. Skinner’s conclusion, in so 
far as it applies to conditions in the latitude of New York State. 
Opposed, is the fact that various experimentors, notably Hewitt 
(1910) and Jepson (1909) wholly failed to carry pupae through the 
winter. 
The house-fly breeds by preference in horse manure. Indeed, 
Dr. Howard, whose extensive studies of the species especially qualify 
him for expressing an opinion on the subject, has estimated that under 
ordinary city and town conditions, more than ninety per cent of the 
flies present in houses have come from horse stables or their vicinity. 
They are not limited to such localities, by any means, for it has been 
found that they would develop in almost any fermenting organic 
substance. Thus, they have been bred from pig, chicken, and cow 
