XXIX. Family PLATYPEZID^. 



Fig. 93. Platypeza, species; enlarged. After Washburn. 



Small, thinly pilose flies, with bristles; especially char- 

 acterized by the ornamentation or enlargement of the 

 hind tarsi. Head hemispherical, as broad or broader 

 than the thorax, and closely applied to it. Face usually 

 short and broad. Eyes bare, contiguous in the male, 

 and in some species in the female also. Ocelli present. 

 Antennae porrect, the first two joints short, the third 

 somewhat elongate, oval, pyriform or conical, with a 

 terminal arista. Thorax rather stout, with distinct bris- 

 tles; scutellum with bristles. Abdomen comparatively 

 short; hypopygium more or less incurved. Legs short 

 and strong; hind legs more or less thickened and the 

 hind metatarsi thickened or variously ornamented in the 

 American forms, the following joints often partaking of 

 their peculiar structure. Wings rather large; third lon- 

 gitudinal vein simple, the fourth sometimes imperfectly 

 furcate ; first posterior cell always open in the margin ; 



241 



