TAXONOMY OF MUSCOIDEAX FLIES — TOWNSEND QI 



sharp, conspicuously more approximated than the rows of facial 

 bristles above them, the vibrissa; strong and decussate. Peristomalia 

 almost straight, nearly parallel, with bristles extending to beard. 

 Epistoma prominent, but not showing greatly in profile owing to 

 strong depression of facial plate. Proboscis short, fleshy, part 

 below geniculation about as long as eye width (in front view), 

 labella well developed ; palpi elongate, rather slender, more atten- 

 uate on basal one-third. Axis of head at insertion of vibrissas very 

 noticeably less than that at insertion of antennae, facial profile gently 

 receding, but quite straight. Antennas inserted above eye middle, 

 at about three-fourths of head height ; second joint about twice as 

 long as first, with a pair of bristles on lower front edge; third joint 

 elongate, wider than second, sides nearly parallel. Arista bare, 

 thickened on more than basal one-half, conspicuously jointed; first 

 joint slightly elongate; second joint elongate, two or three times as 

 long as first, and one-fourth to one-fifth as long as third joint. Eyes 

 thickly pilose, not extending as low as vibrissal angles, inner out- 

 line S-shaped in front view in male, straight in female. Front not 

 strongly prominent in profile, but flattened and sloping straight to 

 base of antennas; at vertex (seen from in front) one-third head 

 width in both sexes, in male suddenly swelling in lateral outline an- 

 teriorly, in female gradually widening anteriorly, almost one-half 

 head width at base of antennas. A strong pair of proclinate, diver- 

 gent ocellar bristles. Frontal bristles in two rows, the inner rows 

 strongly curved and widely divergent below, the outer rows nearly 

 straight ; the lowermost bristle on each side sometimes in line with 

 both rows so as to appear (male) as belonging to either, but belong- 

 ing (as shown in female) to inner row, which descends strongly to 

 point somewhat below insertion of arista. Short fine hairs on para- 

 frontals, long hairs on and in front of ocellar area. The usual 

 strong inner and weaker outer vertical bristles, both reclinate, latter 

 also divergent ; two lightly reclinate upper fronto-orbital bristles, 

 the frontal bristles extending only about half way back from base of 

 antennas to vertex. No middle fronto-orbital bristles in male, two 

 strong, decidedly proclinate ones in female nearly in line with the 

 posterior one of the upper fronto-orbital bristles. Parafacials wide, 

 narrower below than opposite antennal insertion, least width about 

 equal to length of second antennal joint, greatest width bordering 

 parafrontals and not twice as much. Facio-orbital bristles in a 

 median row of about five or six, not so strong as frontal or facial 

 bristles, some fine hairs outside them. Width of cheeks equal to 

 one-third eve height, cheek grooves faint. Lower margin of head 



