88 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5 1 



Subfamily Phoroceratin.e 

 Genus Achaetoneura Brauer and von Bergenstamm 



Achatoneura. — This genus is characterized by having the second 

 antennal joint but little longer than the first, and thus is easily dis- 

 tinguished from Tachina s. str., to which it otherwise bears a strong 

 resemblance. Type is hcsperus Brauer and von Bergenstamm, of 

 North America. T. aletia Riley belongs to this genu-. 



HEMIARGYRA, gen. nov. 



Form Polleiiia-like, eyes pilose, facialia and hind tibiae ciliate. 

 Ptilinal suture bent at a rounded angle in middle superiorly, its ends 

 divergent inferiorly, making the ptilinal area almost triangular in 

 shape and about one-third head width below. Facial plate elongate, 

 not narrowed below, depressed, but not produced anteriorly on lower 

 portion, fossae running full length of plate; foveae shallow, but 

 marking length of third antennal joint; a low, sharp, narrow carina 

 fading out before reaching inferior end of foveae. Facialia sharp- 

 edged, narrow in front outline from being set on edge, with a row of 

 strong bristles running fully half way up and marking the edge, 

 which is nearly straight in outline save for a slight curve inward at 

 lower end, and is closely approximated to suture until it begins to 

 curve. Vibrissal angles quite distinctly removed from oral margin, 

 very faintly pronounced, but slightly more approximated than the 

 rows of bristles above them, the vibrissa? strong and decussate. 

 Peristomalia subparallel in epistomal region, divergent posteriorly, 

 with a row of black bristles extending to beard. Epistoma not 

 prominent, not showing in profile. Proboscis very short and fleshy, 

 part below geniculation hardly as long as eye width, but about as 

 long as the palpi ; labella large, with long hairs ; palpi rather elon- 

 gate, moderately slender, but thickened on apical half. Axis of 

 head at insertion of vibrissa? distinctly less than that at insertion of 

 antennae, facial profile very gently receding, but nearly straight. 

 Antennas inserted about on eye middle, at about three-fifths of head 

 height ; second joint rather short, but about twice as long as first ; 

 third joint elongate, not wider than second, sides nearly parallel, 

 subtruncate at apex. Arista thickened on hardly more than basal 

 one-third, finely short-hairy, basal joints distinct but short. Eyes 

 thickly pilose, extending not quite to vibrissal angles, inner outline 

 appearing slightly bulged on middle by reason of a faint incurvature 

 below. Front (female) not prominent in profile, at vertex (seen 

 from in front) about one-fourth of head width, gradually widening 



