that spread Disease. 



29 



one's hands and face, the lesser house-fly remains mostly on the 

 wing, flying about with a curious darting movement beneath the 

 gas-bracket or electrolier in the middle of the bedroom. The 

 lesser house-fly appears earlier in the year than the common 

 house-fly, and persists later, being still found in dwelling rooms 

 as late as November. The lesser house-fly is closely related to 

 the latrine-fly or privy-fly, Fannia scalaris Fabr., but the latter, 

 although a dangerous disseminator of intestinal disease in villages 

 and camps, is scarcely a house-fly ; it rarely enters houses. 



FIG. 8. COMMON HOUSE-FLY, 



M iisca domestica, female, x 6 ; largely responsible for the spread of typhoid fever 

 and summer diarrhoea. 



Shown in the same case are specimens of two other house-flies, 

 Muscina stabulans Fin., a large fly, not frequent in its occurrence, 

 and Stomoxys calcitrans Linn., commonly termed the stable-fly. 

 This last is a biting, blood-sucking fly, common in the country and 

 in suburbs, and met with sometimes in the middle of large towns. 

 People who do not discriminate between the different kinds of 

 house-fly imagine, when bitten by a Stomoxys , that it is an ordinary 

 house-fly that has become particularly vicious. Critical examination 



