ART. 23 TWO-WINGED DOLICHOPODID FLIES VAX DUZEE 39 



to be three pairs of inner appendages which are yellowish-brown 

 and a central filament extending back about as far as the lamellae. 



Coxae yellow with all their hairs and bristles yellow; middle and 

 hind pairs a little brownish on outer surface. Femora yellow: fore 

 and middle pairs with yellow hairs below; posterior pair brown 

 above for nearly one-third their length and with several black hairs 

 near the tip on lower outer edge. Fore and middle tibiae yellow; 

 hind tibiae blackish, except extreme base; middle tibiae without a 

 bristle below. Fore and middle tarsi yellow, darkened at their tips, 

 the former as long as their tibiae, their joints as 28-10-8-5-6; hind 

 tarsi wholly black, their joints as 24—22-20-7-7. Calypters yellow 

 with extreme tip brown, their cilia yellow. Halteres yellow. 



Wings grayish ; last section of fourth vein a little bent at its mid- 

 dle, parallel with third at tip; crossvein distinctly oblique, not at 

 right angles with fourth vein ; last section of fifth vein a little longer 

 than the first section, nearly straight, one and a half times as long 

 as the crossvein ; anal angle of wing prominent. 



Described from two males taken by Dr. J. M. Aldrich; the type 

 was taken at Lafayette, Indiana, June. 1908 ; the other was taken at 

 Erwin. South Dakota, June 2. Both specimens are in the United 

 States National Museum. 



Ty2)e.—'MA\e, Cat. No. 27052, U.S.N.M. 



35. ARGYRA (LEUCOSTOLA) FLAVICOXA, new species 



Male, — Length, 5 mm. Face and front silvery white, the former 

 moderately narrow. Occiput green with thin white pollen. Palpi 

 yellow with silvery white pollen and a black bristle at tip. Antennae 

 black: first joint bare above; second not as long as wide; third joint 

 slightly longer than the basal two taken together, obtuse at tip: arista 

 subapical, slightly longer than the antenna. Lower orbital cilia 

 yellowish white and short, the very short, black, upper cilia reach 

 down to the middle of the eye height. 



Dorsum of thorax bright green with bronze reflections and abund- 

 ant silvery white pollen; scutellum with one pair of large marginal 

 bristles. Abdomen black, but so thickly covered with silvery pollen 

 as to conceal the ground color when viewed from in front : second 

 segment pale yellow, except a broad median stripe which expands 

 along the hind margin of the segment: third and fourth segments 

 each with a large yellow spot on either side, which reach the posterior 

 edge, but leave a black basal margin on each side ; venter yellow with 

 the last segment brown. Hairs of the abdomen black, except those 

 on the'yellow portion of second segment and on the venter, which are 

 yellow. Hypopygium (fig. 27) black, the small apical portion and 

 the appendages yellow, these consist of a pair of outer lamellae 



