96 DIPTERA 
2. Third antennal joint pear-shaped, nearly twice as long.as wide; 
joints of anterior tarsi rounded-oblong; dorsal process of pygi- 
dium vertically erect, side valves flattened above and with a 
rectangulatlyinbenttip.. . . . . .«. . « - . s. s H. OBLITERATA, Zetterstedt.- 
Third antennal joint short ovate; tarsal joints oblong ; docind process p 
of pygidium bent posteriorly . . . . . jo vl NN T E 
3. Abdomen uniformly though lightly cinereous RM dorsocen- à 
trals blackish; front of female narrowest just above antennae; 
pulvilli one-half (male) or one-fourth (female) the length of the : 
lasttarsaljoint. . . . à . qo . M DE uM tuse iw 
Abdomen polished, at most with faint band binds of pollen on (ilio 
segments; dorsocentrals yellow ; front of female narrowest midway : 
to the ocelli; pulvilli two-thirdsthe length of thelasttarsal joint . . . . . . . . . 5 — 
4. Pygidial valves terminated below by an elongate narrow arm and i 
above byastrong quadrate process . . . . . . . . . . H. CoPULIFERA, nov. sp. (1). 
Pygidial valves lacking the lower narrow arms, but with a long : 
slender erect process arising from base of the L-shaped terminal 
piece . . . « DAT . H. VIRGATOR, nov. sp. (2). 
5. Stigma and veins RSEN judiéres blackish; legs black ipt apex 
ofcoxe and knees. . . . ; e o y A . . H.wiemicaws, Loew.— 
No stigma, veins thin and pale; bálláres d legs yellow to bna RA UNS c E 
6. Robust, 4.5 mm.; abdomen shining black; third antennal joint : 
broadly oval. . . ees s s - « . .H. BULLATA, Melander. 
Smaller, 3-4 mm. ; A CDUNN often biosrid ibd Aus Mes bands of : 
pollen across base of segments; third antennal joint subrotund ; 
(1) Hormopeza copulifera, nov. sp. — Male. Length 4to 5mm. Black, eyes contiguous, third antennal joint 
round, occipital hairs white. Thorax completely coated with cinereous pollen, the prominent setz of middle of notum 
blackish, lateral and posterior bristles pale, Abdomen lightly covered with gray pollen, its hairs pale; pygidium mostly. 
shining, lightly pollinose below, with strong convex lateral valves terminating below in a narrow, incurved, parallel-sided 
brown arm which bears a few long and short setze, and above by a heavy quadrate process which is somewhat expanded at. 
the tip, within the last mentioned process the valve bears a short but strong conical projection, hairs and setze of pygidium 
prominent and blackish. Legs simple, hairs pale in the femoral crests, elsewhere mostly dark, all tibi bearing dark 
bristles, pulvilli dusky, about half the length of the last tarsal joint. Knob of halteres blackish, wings cinereous, almost 
hyaline, veins thin but dark, distal portion of costal cell blackish ; sections of fifth vein 2 : 3. 
Female. Eyes widely separated, front narrowest above antennze, ovipositor retracted in the tubular eigth segment. 
Types taken from a window in a sawmill at Cceur d'Alene, Idaho, 24 August, 1916. Paratypes from Douglas, 
Alaska (E. L. Jenne), Friday Harbor, Washington (J. M. Aldrich), Banff, Alberta (C. B. D. Garrett); and Port Angeles, 
Olga, Friday Harbor, Spokane, Washington ; and Potlatch and Moscow, Idaho (Melander). Most of these specimens were 
taken on windows. 
(2) Hormopeza virgator, nov. sp. — Male. Length 3 mm. Black, eyes contiguous, antenne black, third 
joint round; occipital hairs pale; thorax entirely covered with cinereous dust, hairs of middle of notum blackish, 
lateral and posterior bristles pale; abdomen lightly coated with pollen, subshining, its long, fine hairs white; pygidial 
valves polished, terminating in a broadly L-shaped inflexed flap from the base of which arises a slender, erect, long 
prong, a few long dark setz on lateral valves. Legs simple, hairs yellow, hind femora ciliate above, bristles of 
hind tibie black, pulvilli gray less than one-half as long as last tarsal joint.  Halteres blackish; wings narrow, 
nearly hyaline, veins thin and brown, distal portion of costal cell brownish-gray, sections of fifth vein proportioned 5 : 6. 
Female. Eyes widely separated, the sides of the front diverging from the antennz. Last abdominal segment 
retracted. 
Types, Pullman, Washington, i1 September, 1998, taken from a window. Twenty paratypes from Spokane, 
Washington, and from Potlatch, Chatcolet, and: Moscow, Idaho, the last collected by J. M. Aldrich. Most of the 
paratypes were taken from window-panes, August to October. 
