338 DIPTERA 
vein, first posterior cell widest at its apex, costa thickened 
from the first to the third vein... . . . . . . . . P. BALLISTRARIUS, nOY. Sp. (1). 
Third vein curved, converging with the fourth at the end, 
the first posterior cell widest at the middle, costa not 
greatly thickened. . . UR i anus C TA MIR IP SERERE. 
86. Third and fourth veins HON MEN. the TES IPSE: cell : 
atits middle occupying much more than one-third of the 
WIND. (4 542 55 2 oor uu RC E P LM M 
Third and fourth veins gently but distinctly curved, the 
first posterior cell at its middle occupying not more than 
one-third of wing, third vein ending at or beyond tip 
obwilg ... . ecce Merc era a rp BT e 
87. Anterior femora with bond blackish andi hind feno : 
dark apically ; epistome shining ; tarsi with dark tip; third 
antennaljointsubequal to arista . . . . . . . . . P. vALGUS, nov. sp. (3). 
(1) Platypalpus ballistrarius, nov. sp. — Male. Length 2.5 mm.  Mesonotum moderately dusted with 
olive-gray pollen, its bristles yellow ; wings with long basal cells and costa thickened from the first to the third vein 
Front and face white pollinose, the sides of the front parallel, epistome shining black; palpi small, brown but 
pollinose and with sparse white sete, proboscis black; ocellar bristles small, oae pair o yulow. vertical brise, one ? 
small humeral, three notopleuralo one small postalar, four scutellar, three moderate posterior dorsocentrals, four 
more than two-thirds the length of the Mie d MM black. Second, third and fourth Meno E. t 
the anterior, third vein straight, the fourth vein slightly undulating, the first QUod cell a little the widestatitsend 
which occupies the apex of the wing, sections of the fifth vein proportioned o.8 : tig, PM OE NNI MA NN, 
anal crossvein forming an angle of 60», marginal cilia as long as the anterior crossvein. 
One specimen, Falls Church, Virginia, May 1o, received from Nathan Banks. 
(2) Platypalpus lyristes, nov. sp. — Male. Length 2.5 mm.  Mesonotum with rather dense cinereous 
pollen, the bristles yellow. Face and front white-pruinose, the latter with parallel sides, 5 black; palpi 
oval, one-half as long as the proboscis, white, and with white hairs. proboscis black; antennz two-jointed, black,  - 
the outer joint elongate lanceolate, nearly four timss as long as wide and a little longer than the arista; ocellar 
bristles small, two pairs of vertical bristles, One humeral bristle, notopleurals small, one supraalar, one postalar, 
two dorsocentrals, lateral scutellars small, acrostichals biseriate; sternopleural spot moderately large, pentagoual; 
abdomen including the venter shining black, base of the segments with indications of pollen, hairs sparse 
above, subdorsal pits prominent, upper valves of the pygidium broad, densely fringed on the left side with long 
golden cilia Legs including the coxa yellow, tarsi scarcely darker apically, anterior E loosel below, 
middle femora with but about sixteen set in the posterior flexor row, setulz of middle legs min z 
five-sixths as long as the femur, the spur longer than the diameter of the tibia and tipped with b 
pale at the base, darker distally, the costa brown beyond the first vein and not swollen, crossveins meeting, both 
long, subequal and nearly transverse, third and fourth veins mutually bowed, the basal and first ——GÓ — 
unusually wide, occupying more than one-third of the wing, sections of the fifth vein proportioned r : f 
marginal cilia short. 
One specimen, Bright Angel, in the Colorado Canon, Arizona, elevation 3700 feet, collected by H. S. Barbor 
for the U. S. National Museum. 
n 
(3) Platypalpus valgus, nov. sp. — Male. Length 2.6 mm. Black, legs mostly yellow, the anterior 
femora broadly annulate, the hind femora dark on the outer half, tibial spur strong, mesonotum with golden 
pubescence, crossveins at the middle of the wing, meeting and transverse.  Occiput olivaceous pollinose, lower 
hairs silky white, two black verticals and one ocellar; front similarly pollinose, face white, epistome bare; palpi 
small, brownish in ground color, proboscis black; antennz black, the third joint hairy below, slender, two and a : 
half times as long as wide and two-thirds the length of the arista. Lateral thoracic bristles brown, two 
dorsocentrals, acrostichal and dorsocentral setule in single rows, pleure gray pollinose, half of the sternopleure 
shining. Abdomen shining, base of the second segment laterally lightly pollinose, hairs rather long and pale, 
pygidium obliquely ascending, left dorsal :valve triangular, pointed, its fringe dense and yellow. Anterior legs 
- 
Mec 
