THE DUNG FLIES 255 



and Australia, a very general scavenger, is known as 

 Sarcophaga carnaria L., and in countries which it in- 

 habits is once in a while found in houses. It does not 

 seem to occur in the United States, although a species 

 which much resembles it, S. sarracenice Riley, is abun- 

 dant throughout the country. It looks like a very large 

 and active house fly, and is occasionally found in 

 houses. It is commonly reared from the remains of 

 dead insects, but is also attracted to and breeds in ex- 

 creta. (Fig. 31.) 



A smaller species, 5*. assidua Walk., much resembles 

 the house fly and is of about the same size. - It is con- 

 fined to the United States and is occasionally found in 

 houses. It, like the preceding species, breeds in dead 

 insect remains, but is attracted to and breeds in ex- 

 creta and is therefore dangerous. 



THE DUNG FLIES ' 

 (Sepsis violacea Meig., Scatophaga furcata Say) 



There is a little black fly known as Sepsis violacea 

 Meig., which is shown in Fig. 32 and which is not at 

 all uncommon in houses, being found as a rule upon 

 the window panes. It belongs to the same family as 

 the cheese fly, but does not attack stored foods or any- 

 thing to be found in the pantry. It breeds almost ex- 

 clusively in excreta and has been reared in swarms 

 from an old human deposit collected on the Potomac 

 flats near the city of Washington. It is very small in 

 size, glistening black in color, and of slender shape. 



There is a whole family of small, brownish flies 



