30 INSECUTOR INSCITI^ MENSTRUUS 



head-height, stout; palpi rather stout, a little shorter than 

 third antennal joint, thickened distally. Sternopleurals, post- 

 suturals, and postacrostichals all three in number. Scutellum 

 with four laterals, the front and hind ones longest, latter reach- 

 ing to base of third segment; a weak erect decussate apical 

 pair, and an approximated weak discal pair, with some addi- 

 tional discals in male. Whole form narrowed, abdomen about 

 same width as head and thorax. Venter of female is not 

 carinate (stated by Coquillett to be carinate, 1. c). Abdominal 

 macrochsetse discal and marginal, the latter long, the discals 

 short, all erect ; median marginal pair on first segment ; no 

 marginals on anal segment of female, except short ones like 

 the discals, but anal segment of male is well covered with 

 strong ones. Hind tibise not ciliate or pectinate. Apical cell 

 ending well before wing-tip, closed or narrowly open; cubitus 

 angular, with faint wrinkle ; apical crossvein only slightly bent 

 in and subparallel with hind one, which is nearer to cubitus ; 

 strong costal spine. Third vein spined nearly halfway or 

 almost to small crossvein, other veins bare. Last section of 

 fifth vein is almost half as long as preceding section. Legs 

 of moderate length; claws of female nearly or quite as long 

 as last tarsal joint, those of male distinctly more elongate. 

 Neothelaira aurifrons Coquillett. 



Length of body, 9 mm. (females rather flexed) ; of wing, 

 6.5 mm. One female, holotype of dexina, TD427, Lynn, 

 Massachusetts, August 28, 1908 (F. B. Lowe) ; holotype of 

 aurifrons, female, Mount Washington, New Hampshire (Slos- 

 son) ; allotype, male, White Mountains, New Hampshire 

 (Morrison). 



Entire parafacials, cheeks, occipito-orbits, vertex, and para- 

 frontals deep rich gold in female, the whole facial plate and 

 facialia gold to gray-golden; in male more obscurely golden, 

 the parafrontals largely blackish; frontalia and arista dark 

 brown; antennae blackish, the first two joints and base 

 of third rufous; palpi pale rufous. Occiput silvery- 

 cinereous. Thorax, scutellum, and abdomen shining 

 black, silvery pollinose ; mesoscutum with four vittae, the outer 



