FAM. EMPIDIDZE 321 
15. Legs entirely black; third antennaljointoval . . . . . P. woNrICOLA, Melander. 
Tibia and front knees brown, tarsi annulate; third antennal 
feJanceolate o EL o oos ere oor R LES INEBRIALIS, nov. sp. (1). 
TIO Lupi osellowTD Ia perpart: velis yellowish. .. s.a exules tomus e aT o T4, 
Thorax wholly black, although more or less overlaid with 
BUE polen Mr. M MD ad edu Du REDE t. DS. 
17. Head entirely yellow; front femora with seriateflexorbristles . . . . . . . . . . . A8. 
FHendiglobular; theloccipht at leasP black. 2 E eio D Su Te eU SABA Ee 29. 
18. Spur of middle tibie strong; posterior crossvein oblique and 
distant from anterior; sides offrontnearlyorquiteparalel . . . . . ... . . . . rg. 
Spur of middle tibia undeveloped; crossveins meeting, the 
posterior transverse; head globular, sides of front diverging 
abaves cd ceras M ML oni wien E. DECOLOR;DOV.. sp. (2): 
19. Head globular; antenne tipped with black; thorax shining; 
Iuird velnecurved -—. 0.25 E uus iR 2s pP Urt P. MBELEUS, nov.:sp. (3). 
(1) Platypalpus inferialis, nov. sp. — Léngth 2.2 mm. Occiput cinereous, one pair of brown vertical 
bristles, frcnt and face cinereous when viewed from above, white when seen from below; palpi one-third as long 
as the proboscis, whitish and with a few white hairs; third antennal joint lanceolate, twice as long as broad, the 
arista slightly longer than the antennz. Dorsum of the thorax shining black except that the lateral and posterior 
margins are cinereous pollinose, its hairs and bristles fine and yellow, one dorsocentral, one supraalar, one notopleural 
and two pairs of scutellar bristles; pleure whitish pruinose, the notopleural suture more olivaceous, sternopleurze 
with large triangular shining space; abdomen subshining, its hairs not long, the pygidium rather small, the terminal 
valve with a fringe of silky hairs above and the left valve similarly fringed beneath. Front and middle femora 
stout, with long loose white seriate hairs beneath, spur of the middle tibie large; femora black, knees and tibiae 
brown, the hind pair darkest, tarsi annulate, but usually the black predominating. Costa thickened at the end of 
the first vein, its second, third and fourth sections proportioned 3.5 : 2.5 : 1, fourth vein slightly sinuous but in 
the main subparallel with the third, posterior crossvein oblique, separated from the anterior by one-half the length 
of the anterior crossvein, sections of the fifth vein proportioned nearly 3 : 2, anal crossvein located at one-third 
the length of the second basal cell, nearly perpendicular, anal vein indicated merely by a f[old. 
Numerous specimens, type from Almota, Washington, April 17. Paratypes from Pullman and Oroville, Washington 
(Melander) and Juliaetta, Idaho (J. M. Aldrich). 
(2) Piatypalpus decolor, nov. sp. — Female. Length 2.5 mm. Entirely pale yellow, the arista, ocellar spot, 
apex of abdomen and last tarsal joint alone brownish. Head globular, sides of the pollinose front diverging, epistome 
shining, palpi small; last antennal joint slender, lanceolate, two and a half times as long as broad and slightly 
longer than the short-pubescent arista. Mesonotum polished except along the sides where it is lightly dusted, 
nearly bare, the few hairs seriate, humeral bristle strong, middle scutellars long; pleure dusted except most of the 
sternopleure; abdomen shining. Legs slender, front femora biseiately fringed beneath with about ten bristles, 
middle femora with about eighteen slender spinules in each flexor row, those behind longer, middle tibia obliquely 
truncate without spur. Veins pale yellow, crossveins at two-fifths the wing-length, the posterior transverse and 
slightly proximal to the anterior, first posterior cell ending at the wing-tip, its veins parallel, base of the anal 
vein weakly indicated, anal crossvein slightly recurved, sections of the costa proportioned 6 : 4 : 2 : r. 
Two specimens, Foot of Lake McDonald, Glacier National Park, Montana, August 14, 1916 (Melander). 
(3) Platypalpus melleus, nov. sp. — Female. Length 2 mm. Yellow, the ocellar spot, outer half of 
the third antennal joint with the arista, the eyes, flexor setule of middle legs, apex of tibial spur and last 
tarsal joint alone blackish. Back of occiput shining, front and face moderately broad, white, the face three-fourths 
as long as the front, epistome shining; third joint of the antenna pyriform, one-half longer than broad and about 
one-third as long as the arista, Thorax shining above, setulee very sparse and small, pleure white-pruinose except 
the moderate sternopleural spot; abdomen shining except the last two segments. Legs rather slender, the middle 
femora moderately inflated, front femora scarcely ciliate, middle femora with a posterior row of eight silky yellow 
sete, middle tibiae two-thirds as long as their femora. In :ersws the front femora are somewhat swollen and ciliate, 
and the middle tibie& are three-fourths as long as their femora. Wings narrow, the second, third and fourth sections 
of the costa proportioned 4.5 : 3.5 : r, third vein recurved but ending just before the tip of the wing, posterior 
crossvein slightly oblique, located its own length beyond the anterior and at three-sevenths the length of the wing, 
anal crossvein perpendicular. sections of the fifth vein proportioned 0.4.: 0.6 : 1, base of the anal vein wanting, 
marginal cilia as long as the anterior crossvein. 
One specimen, Gowanda, New-York, received from M. C. Van Duzee. 
