296 DURHAM DIPTERA. 



XXXIV. 



57 (54). Shorter built species, not unusually long bodied ; 



abdomen not extending much beyond the tip of 

 the hind femora. 



58 (59). Third antennal joint rounded in front ; mouth with 



one strong bristle on each side. 



Microprosopa, Beck. (493) 



59 (58). Third antennal joint with a sharp upper corner. 



60 (63). Acrostichal bristles in two rows ; dorsum and legs 



thinly and not long haired. 



61 (62). Antennae small with very . sharp points ; jowls not 



broad; two bristles on each side of the mouth ; arista 

 normal, only thickened at the base ; small, short, 

 grey dusted species. Trichopalpus, Rnd. (494) 



62 (61). Antennas large and broad, rounded in front; jowls 



broad ; only one bristle on each side of the mouth ; 

 arista thickened almost to the tip. Acerocnema, 

 Beck, (breviseta, Ztt., with a grey dorsum and two 

 dark lines, grey orbits, short haired abdomen, and 

 bristly legs; tiefi, Beck., with a shining black 

 dorsum, black orbits, shorter haired abdomen and 

 legs not bristly; and both of them with a bare 

 arista, and palpi very broad at the ends ; pokornn, 

 Beck., with the palpi more dilated throughout, and 

 the arista distinctly haired). 



63 (60). Acrostichal bristles in several irregular rows ; dorsum 



and legs strongly haired ; mouth bristles numerous ; 

 abdomen flat; genitalia not much protruding; 

 femora strong, finely haired and weakly bristled ; 

 jowls broad. Spathiophora, Rnd. (495) 



64 (39). Head round, not specially broad ; palpi filiform, 



seldom strap-shaped. 



Sub-Family IV. — Scatophagin^e. 



65 (66). Abdomen in the male cylindrical, and with erect, 



usually thickly set hairs, the end not much bent in- 

 wards, and the segments without marginal bristles ; 

 flat, with short depressed hairs and with marginal 

 bristles in the female. Scatophaga, Mg. (496) 



