IQ PROCEEDINGS OF THE NATIONAL MUSEUM tol. 79 



Legs black; mid tibiae usually with one stout and one or more 

 smaller bristles (sometimes only one large) on outer front side near 

 middle ; hind tibiae thickly ciliate with or without one longer bristle 

 in the row ; claws and pulvilli elongate. 



Wings grayish hyaline with a brown tinge at base; fourth vein 

 with a sudden oblique bend curving inward beyond reaching costa 

 well before wing tip; third vein with one or two hairs at base; 

 costal spine minute. 



Female. — Front 0.313 of the head width (average of three), gray 

 poUinose with a perceptible yellowish tinge ; face and cheeks cinere- 

 ous; the usual two pairs of orbitals present; inner verticals strong, 

 outer ones only slightly smaller, curving outward ; wing shorter and 

 broader apically than in male; third antennal joint wider than para- 

 facial below; claws and pulvilli short. 



Length, 7 to 10.5 mm. 



Kedescribed from 39 specimens including several (both sexes) 

 from Europe determined by Dr. J. Villeneuve. Distribution: New 

 Hampshire (C. H. T. Townsend, Mrs. A. T. Slosson) ; Indiana, 

 North Dakota, Idaho, Oregon, Washington (J. M. Aldrich) ; Illinois 

 (Charles Robertson, W. A. Nason) ; Wisconsin, no collector's label; 

 New Mexico, 6,500 and 7,000 feet (C. H. T. Townsend). 



(5) WINTHEMIA IGNOBILIS van der Wulp 



Exorista igno'biUs van der Wulp, Biologia Dipt., vol. 2, p. 71, 1890. 



The type, a male specimen from Amula, Guerrero, Mexico, is in 

 the British Museum. I have not seen it, but determine the species 

 from notes taken on the type specimen by Dr. J. M. Aldrich in 1929. 

 The female sex is unknown to me. 



Male. — Front moderately broad, before ocelli 0.233 of the head 

 width (average of three: 0.25; 0.22; 0.23), rather protuberant below; 

 parafrontals with plumbeous pollen becoming thinner upward and 

 almost shining black before vertex, thickly clothed with longish up- 

 right hairs; median stripe blackish, wider than one parafrontal at 

 antennae; verticals two pairs, the outer about three-fourths as long 

 as inner ones; orbitals none; ocellar bristles well developed; frontal 

 bristles 12 to 14 in number, reduced in size above and stopping 

 before triangle, the lowermost nearly on level with apex of second 

 antennal joint; face plumbeous pollinose, the sides moderately broad 

 and thickly hairy ; antennae black, second joint three-fifths as long as 

 third; arista black, longer than antennae, thickened on basal two- 

 fifths, penultimate joint slightly longer than wide; vibrissae situated 

 a little above the front edge of mouth ; palpi wholly black or yellow 

 apically, rather slender, beset with numerous black hairs; cheeks 

 black and subshining but with thin pollen apparent in certain views, 



