440 THE NOBTR AMERICAN EMPID.T.—COQUILLETT. vol. xviii. 



Wings brown, the base, except a border to the fifth vein, white; anal cross 

 vein present ; legs wholly black, hal teres whitish, inner sides of middle 

 tibia} not emarginate before the ti])s cJaripes. 



Wings hyaline, base white, a black spot at last third of the costal margin, 



legs and antennie wholly black macidipennis. 



AVings brownish, the base white, anal cross vein jiresent, juiddle femora yel- 

 low, inner sides of middle tibia^ of male emarginate near the tips 3 



Wings wholly gray or brownish 4 



3. Front and hind femora marked with black rapax. 



Front and hind femora wholly yellowish rosirata. 



4. Femora and antenna' wholly black 5 



Femora, or at least the front and middle ones, partly or wholly yellow, mid- 

 dle femora wholly yellow 6 



5. Tibite and knob of halteres yellow portacola. 



Tibite and halteres black win ihemi. 



6. Front femora marked with black 7 



Front femora wholly yellow, legs yellow, the hind ones black, halteres and 



antenme whitish jyosttca, 



7. Tibiie yellow, the middle and hind ones partly black, halteres and antennfe 



yellow similis. 



Tibiie wholly yellow, scutellum bispinose fenesirata. 



TACHYDROMIA SCHWARZII, new species. 



Male and female. — Head black, opaque gray pollinose, the clieeks shill- 

 ing; autennre yellowish, the third joint short conical, the apical arista 

 bristle-like, four times as long as the auteun;e; palpi nearly as long as 

 the proboscis and appressed to it, their front part densely covered with 

 appressed silvery-white pile in the male. Thorax, pleura, scutellum 

 and abdomen shining black. Legs dark brown ; bases of tibia? and of 

 tarsi, and sometimes of the femora, yellowish. Knob of halteres 

 whitish. Wings whitish, ci'ossed by two broad, browu cross bands, the 

 first extending from base of second vein to slightly beyond the posterior 

 cross vein, the second extending from slightly beyond apex of fifth vein 

 to a sliort distance beyond the tip of the second vein, leaving the base 

 of the wing, a cross band just beyond the middle, and the tip of the 

 wiug.Avhitish; anal cross vein wanting, the other two of an equal length, 

 the distance between them snbequal to that between the small cross 

 vein and base of the third vein, the second basal cell being much 

 longer than the first: distance between tips of third and fourth veins 

 Cipial to one-third of that between the second and third veins; mar- 

 ginal cell about one-half as wide as the submarginal. 



Tj/pe.s.— Xos. 3246 and 3247, U.S.X.M.; male and female; length, 2J 

 mm. The Utah specimen was collected June 20, by Mr. E. A. Schwarz, 

 after whom I take ])leasure in naming this handsome species. 



Locality. — Northern California and Utah. 



