The Fly: Pest of the Household

The most common fly found in houses is the species known as the House Fly (Musca domestica Linn). It is of medium size, grayish, and has mouth parts dilated at the end in a sort of lobe, fitted for taking up liquid food. Its early stages are passed in moist, decaying matter, especially horse manure or other excrement. These flies never bite; but they are pernicious visitors because of their filthy habits, and their known agency in the dissemination of disease.

A second species, the Stable Fly (Stomoxys calcitrans Linn), is the pest that annoys us by biting, especially before storms. It has piercing mouth parts.

Other species often are observed, but the two named above are the biggest majority, and of these two the house fly is by far the more numerous.

Since flies are known to carry disease, it is of prime importance to be rid of them in our homes. Proper screening is the first requisite, and nothing can be accomplished without this fundamental protection. But in addition we must look to the breeding places, especially manure heaps. Usually the most feasible plan of caring for these is to enclose or otherwise screen them. If the manure can be removed once a week, flies cannot complete their life round in it.

An effective means of poisoning flies that have already gained access to a room is as follows: Add two tablespoonfuls of 40 percent formalin to one pint of sweet milk, or equal parts milk and water. Pour this out in shallow plates, so that flies can get at it easily. A piece of bread placed in the middle of each plate will allow more space for flies to alight and feed.

Catching flies by means of traps or with sticky fly paper, is a universal practice, and helps reduce the numbers within a room, but the method described above will usually be found more rapid and effective.