99 
19. Palpi yellow on at least the apical two-thirds 22. 
Palpi, except the tips, black 20. 
20. Middle tibiae each, bearing two or more rnacrochaetae on the front 
side near the middle 21. 
Middle tibire each bearing a single macrochaeta on the front side near 
the middle; black; front of male three-fifths as wide as cither 
eye, frontal bristles descending to the arista, no orbital bristles, 
hairs of front numerous and rather long, cheeks one-eighth as 
wide as the eye height, vibrissas on a level with front edge of 
the oral margin, ridges bristly on the lowest fourth, antennae 
almost as long as the face, the third joint six times as long as 
the second, arista thickened on the basal fourth, thorax whitish 
pollinose, marked with four biack vittse, scutellum bearing three 
marginal pairs and a short, cruciate apical pair of macroclneta 1 , 
the latter curving backward and nearly horizontal; abdomen 
shining, with a brassy tinge, narrow bases of the second and 
third segments whitish pollinose. each segment bearing mar- 
ginal macroclneta', the bristly hairs rather long and suberect; 
front pulvilli slightly longer than the last tarsal joint; wings 
hyaline, third vein bearing two or three bristles near the base; 
calypteres white; length, 7 mm. Tifton, Ga. A male specimen 
collected October 17, 1896, by Mr. ( I. K. Pilate. Type No. 3598, 
U. S. National Museum polita n. sp. 
21. With four postsutural macrochaetae (see under 17) futilis O. S. 
With only three postsutural macrochaetae, front in male four fifths 
as wide as either eye, his third antennal joint three and one- 
half times as long as the second, several macrochaetae outside 
of the frontal bristles; length, 10 mm. Texas. (Biologia Cent.- 
Amer., Vol. II, p. 70; February, 1890.) angustata v. d. \V. 
22. Thorax bearing four postsutural macrocha'ta^, abdomen not tinged 
with bronze, apical cell open 21. 
Thorax bearing only three postsutural macroclueta*, scutellum 
black, middle tibia' each bearing a single macrochaeta on the 
front side near the middle 23. 
23. Apical cell closed and short petiolate, abdomen strongly tinged with 
bronze; black, the palpi yellow; front of female one and one- 
sixth times as wide as either eye, the sides bearing numerous 
short hairs, two pairs of orbital bristles in the female, frontal 
bristles descending almost to apex of second antennal joint, 
cheeks nearly one-fourth as wide as the eye height, facial ridges 
bristly on the lower half: antennae five-sixths as long as the 
face, the third joint three times as long as the second, arista 
thickened on the basal third, the penultimate joint slightly 
longer than wide; thorax gray pollinose, marked with four 
black vittae, scutellum bearing three long marginal and a short 
apical pair of macrochaetae, abdomen gray pollinose on the 
bases of the last three segments, its hairs closely appressed, 
