NO. 2152. NEW MUSCOID FLIES— TOWNSEND. 323 



second and third segments are nearly same length, the fourth is much 

 longer; the fifth is shorter than fourth, but with arcuate front border 

 increasing its tergal length on mechan line. No discal macrochaetae, 

 no median on first tlu-ee segments. Basal segments of hypopygiiun 

 exposed with full posterior aspect, not ventral. Claws not much 

 longer than last tarsal joint. Apical cell closed a little before wing- 

 tip, hardly petiolate; cubitus m a broad gentle curve, apical and 

 huid cross vems parallel with hind margin of wing, the hind cross vein 

 very sinuate and close to cubitus. Small cross vein opposite end of 

 first vein. Tegulae small. 



FORMICOPHANIA ELEGANS, new species. 



Length of body, 12 mm.; of wing, 9 mm. One male, Khow Sai 

 Dow, 1,000 feet, Trong, Lower Siam, Jan.-Feb., 1899 (W. L. Abbott). 



Head black, thinly silveiy, the parafaoials and cheeks showing 

 more heavily silvery-white. Palpi, antennae, thorax, and scutellum 

 black, with thin silvery coat; vittae of mesoscutum coalesced, forming 

 a pair of very wide heavy black vittae before suture and separated by a 

 brassy median vitta, joined in an unbroken black behind suture. 

 Humeri brassy. Posterior margin of first abdominal segment, all of 

 second, and broad anterior border of thhd deep yellow, the third with 

 silvery-white pollen over the yellow; rest of abdomen soft black, the 

 fifth segment with pale golden pollen visible in oblique view. Hy- 

 popygium rufous. Hind legs mostly yellow, the others mostly dark 

 brown ; the front tibiae and tarsi mostly yellowish, the middle femora 

 considerably yellow. Wings deeply infuscate on costal half, the 

 discal cell and a subcostal streak yellowish. Tegulae whitish. 



Holotype.—No. 20052, U.S.N.M. 



