present they eventually die. However, where they have access to both
food and suitable substances for egg laying they will continue breeding
just as they do outdoors during the summer. Even in very cold climates
there are undoubtedly many places, especially in cities, where house
flies would have opportunity to pass the winter in this manner.




CARRIAGE OF DISEASE BY THE HOUSE FLY.


The body of the house fly is covered thickly with hairs and bristles of
varying lengths, and this is especially true of the legs. Thus, when it
crawls over infected material it readily becomes loaded with germs, and
subsequent visits to human foods result in their contamination. Even
more dangerous than the transference of germs on the legs and body of
the fly is the fact that bacteria are found in greater numbers and live
longer in its alimentary canal. These germs are voided, not only in the
excrement of the fly, but also in small droplets of regurgitated matter
which have been called "vomit spots." When we realize that flies
frequent and feed upon the most filthy substances (it may be the excreta
of typhoid or dysentery patients or the discharges of one suffering from
tuberculosis), and that subsequently they may contaminate human foods
with their feet or excreta or vomit spots, the necessity and importance
of house-fly control is clear.

In army camps, in mining camps, and in great public works, where large
numbers of men are brought together for a longer or shorter time, there
is seldom the proper care of excreta, and the carriage of typhoid germs