PAET lY 



OTHER SPECIES OF FLIES FREQUENTING HOUSES 



CHAPTER XV 



THE LESSER HOUSE-FLY FANNIA CANICULARIS L^. 

 AND THE LATRINE FLY, F. SCALARIS FAB. 



The two species of flies Fannia canicularis L. and F. scalers 

 Fab. are, on account of their habits, of considerable economic im- 

 portance in their relation to man. They belong to the dipterous 

 family Anthomyidae, many of which resemble the house-fly in 

 general appearance, on which account F. canicularis is very fi*e- 

 quently mistaken by the uninitiated for M. domestica which are 

 not full grown or "young" house-flies. They are characterized 

 chiefly by the close approximation of the eyes of the male, the 

 comparatively large squamae or lobes on the posterior sides of 

 the bases of the wings, and the open first posterior or apical 

 cell (5 R.) of the wing (cf. fig. 7). Most of the larvae feed upon 

 decaying vegetable or animal substances. 



Without close examination, the tAVO species under examination 

 are liable to be mistaken for the same species, but such an exami- 

 nation will serve to separate them. The abdomens of both species 

 are conical, but the basal segments of the abdomen of F. canicu- 

 laris are partially translucent, and the abdomen of F. scalaris is 

 black overspread with bluish gi^ey ; each of the mid tibiae of the 

 latter species bears a distinct tubercle which is not found in 

 F. canicularis (fig. 81). 



^ Until recent years this species has always been referred to as Homalomyia 

 canicularis, but by the rules of priority the generic name Fannia of Eobineau 

 Desvoidy, 1830, which was given in his Essai sur les Myodaires, will have to replace 

 Bouche's genus Homalomyia, by which generic name these species have been 

 previously designated but which genus was not created until 1834. 



