256 THE HOUSE FLY DISEASE CARRIER 



known as the Scatophagidae, which, as the scientific 

 name indicates, are attracted to and breed in the dung 

 of different animals, and also to some extent in decay- 

 ing vegetable material. They are, as a rule, rather 

 light-colored, bristly flies. The species shown at Fig. 

 33 is known as Scatophaga furcata Say. It is a North 

 American species of rather wide distribution, which 

 in its early stages lives in all sorts of excreta and is 

 once in a great while found in houses. It does not 

 hibernate as an adult fly, but in its puparia in dung. 



THE MOTH FLIES (Psychoda minuta Banks) 



There are certain very minute flies belonging to a 

 family known as the Psychodidae, which are very pe- 

 culiar from the fact that they resemble little moths, 

 their broad wings being covered with hairs, making 

 them look like moths. They are very weak fliers, and 

 are frequently found upon windows and on the under 

 surfaces of leaves. They are so small and fragile that 

 they are difficult to capture and preserve. What they 

 do in houses no one knows, unless possibly they enter 

 them for protection. The larvae of some species breed 

 in excreta; others in decaying vegetation, and still 

 others in water, sewage-polluted water being preferred. 

 Psychoda minuta Banks has been reared from cow 

 dung at Washington. None of the North American 

 species has the blood-sucking habit, although a genus 

 (Phlcebotomus) which occurs in Southern Europe and 

 in other parts of the world bites human beings and 

 has been accused of disease-carrying probabilities. 



