_— 
100 
the fourth segment bearing a discal and a marginal row of ma 
crochet; wings liyaline, third vein bearing three bristles near 
its base, bend of fourth vein not appendiculate, this vein 
nearly straight after the bend; calypteres white; length, 
7mm. Northern Hl A female specimen collected by W. A. 
Nason. Type No. 3599, U. 8. National Museum. ..crata n. sp. 
Apical cell open, abdomen not tinged with bronze; black, the palpi 
and inner side of each antenna largely yellow, sides of front 
bearing only a few short hairs, cheeks one seventh as broad as 
the eye height, facial ridges bristly on the lowest fifth, third 
joint of antennze slightly over twice as long as the second, 
thorax marked with three black vittze, scutellum bearing two 
long and an intermediate short pair of marginal macrochete, 
abdomen on the last three segments gray pollinose and with 
numerous reflecting black spots, third vein of wing bearing a 
single bristle near its base, fourth vein strongly curved inward 
beyond the bend; length, 4 mm., otherwise as above descrip- 
tion of wrata. Colorado. A female specimen collected by Carl 
F. Baker. Type No. 3600, U.S. National Museum. . parva n. sp. 
24. Middle tibiwe each bearing a single macrocheta on the front side 
near the middle, third joint of antennie in each sex four times 
as Jone asthe-secomd 22.00 ies Peyote Ste es eee eee 25. 
Middle tibie each bearing two or more macrochete on the front 
side near the middle, scutellum largely yellow, pollen of body 
gray, front in male three-fifths, in the female two-thirds, as wide 
as either eye, third joint of antenne in the male three and one- 
half, in the female three, times as long as the second; length, 6 
toll mm. Canada; White Mountains, New Hampshire; New 
Bedford, Mass.; Clementon, N. J.; Maryland; District of Co- 
lumbia; Virginia; Dayton, Ohio, and St. Louis, Mo. (Trans. 
Amer. Ent.Soc., Vol. XIX, p.287; December, 1892. JMJyxexorista 
sp., Brauer and Bergenstamm in litt. Sisyropasp., Brauer and 
Bersenstamm on litt.) 22,0282 as es ee eudrye Town. 
25. Seutellum largely yellow; hairs on basal half of fourth segment of 
abdomen two-thirds as long as the macrochete, front in the 
male three-fifths, in the female two-thirds, as wide as either 
eye, the sides olive gray pollinose and bearing numerous 
nearly erect short hairs; length, 6 to 9 mm. District of Colum- 
bia; Jennings, Va.; Fort George, Fla.; and Miss. (Biol. Cent.- 
Amer., Diptera, Vol. II, p. 69; February, 1890. Myxexorista 
sp., Brauer and Bergenstamm in litt.)..... flavirostris v. d. W. 
Scutellum black; hairs on basal half of fourth segment of abdo- 
men one-third as long as the macrochete, front in the male 
two-thirds, in the female one and one-sixth times, as wide as 
either eye, the sides silvery gray pollinose, bearing a few very 
short inconspicuous hairs; black, the second antennal joint, 
apex of proboscis, and the palpi yellow; two pairs of orbital 
