324 DIPTERA 
29. Proboscis entirely black; spur of the middle tibiz large; anal 
crossvein perpendiculat. |. . 4 — P6 UH 0. 9nd UV Ln LE EE 
Proboscis yellow; tibial spur rather small; first posterior cell 
not much narrowed . . . . Mu cU LE AL CEA Ier xA Uu 
3o. Mesonotum shining, pleurz mostly adit first posterior cell 
somewhat narrowed in the margin; tarsi weakly annulate. R. LxTus, Loew. 
Mesonotum dusted, subshining, pleurz pruinose except the 
sternopleural spot; fourth vein not noticeably curved 
forward; tarsi notatallannulate. . . . . - « ». P. LETABILIS, nov. sp. (1). 
31. Front narrow, its sides nearly parallel; antenna ; solicili 
yellow; base of the anal vein wanting . . . . . Jo. QT v. C A MEI EI ESSE ENEG 
Front rather broad, its sides diverging above; third PNEU 
joint blackened; anal crossvein oblique, anal cell closed, 
crossveins nearly meeting (P. flavsirosiris, Loew) - .. .. . 2. 4 V. eoa Jd. 
32. Anal crossvein perpendicular, crossveins separated. . . . P. wiMUs, nov. sp. (2). 
Anal crossvein oblique, crossveins meeting; penis hook-like, 
right valve with thorn-tipped process . . . . . . . P. UNCINATUS, nov. sp. (3). 
abdomen glistening, yellow at base and apex, the fourth and fifth segments blackish, the third segment somewhat 
brown, Legs yellow, the last tarsal joint dusky, middle femora with sixteen minute black setulw on the antero-flexor 
edge, twenty on the postero-flexor edge, in back of which are about nine long yellow bristles, spur of middle 
tibie long, acute and tipped with black, Wings yellowish hyaline, veins pale, the third and fourth veins parallel, 
the first posterior cell ending full at the tip of the wing, posterior crossvein beyond the anterior by the length of 
the latter, sections of fifth vein equal, anal vein weak. 
One specimen, Pullman, Washington, June 16, 1912 (Melander). 
(1) Platypalpus laetabilis, nov. sp. — Female. Length 3.2 mm. "Very close to la/ws, differing in having 
the mesonotum dusted so as to be subshining, the pleurz completely white-pruinose except for the sternopleural 
spot, and the third and fourth veins subparallel towards the end. Head cinereous, body testaceous, front and face. 
narrow, densely white-pruinose; proboscis black, palpi white; third antennal joint blackish, ovate, one-half longer 
than wide and one-half as long as the arista. Thoracic setule very sparse; abdomen shining except the terminal 
segments, Front femora with sixteen flexor cilia; middle femora yellow-setose in back, middle tibize two-thirds as 
long às their femora, the terminal spur long and sharp and tipped with black, last tarsal! joint blackish, otherwise 
the tarsi not annulated. Segments two, three and four of the costa proportioned 5:3: 1, first vein a little thickened 
apically, crossveins almost meeting, the posterior slightly oblique, located at three-sevenths the length of the wing, 
sections of the fifth vein proportioned 0.6: 0.8: 1, anal crossvein perpendicular, base of the anal vein very weak. 
One specimen, South Wales, New-York, presented by M. C. Van Duzee. 
(2; Platypalpus mimus, nov. sp. — Female. Length 2 mm. Pale yellow, the arista and occiput 
gray. the minute flexor setule of the middle legs black. Front and face narrow, white, their sides subparallel ; 
antennz' whitish, the third joint ovate, three-fifths as long as the arista; lower occiput and proboscis yellow, 
palpi small and white. X Mesonotum very lightly dusted, a little more pronounced on the humeri, subshining, 
setulie very sparse, humeral bristle large; pleurz finely white-pruinose except the sternopleural spot; abdomen 
shining to the end. Anterior femora moderately thickened, the front ones with a dozen small flexor cilia, the 
middle ones with a posterior row of fine pale setz, middle tibiz two-thirds as long as their femora, the termina. 
spur short blunt and yellow. Wings narrow, third and fourth veins parallel, second, third and fourth sections of 
the costa proportioned 3.5 : 2.3 : 1, posterior crossvein located at three-sevenths the winglength, slightly oblique, 
placed beyond the anterior a distance equal to the latter, sections of the fifth vein proportioned 0.5 : 0.6 : r, 
anal crossvein almost perpendicular, base of anal vein completely wanting, marginal cilia equal in length to the - 
anterior crossvein. 
Two specimens received from M. C. Van Duzee, who collected them at Gowanda and Niagara Falls, 
New York, June. 
(3) Platypalpus unocinatus, nov. sp. — Male. Length 2.2 mm. Light yellow, head black, occiput 
subshining, front narrow, shining, but slightly divergent above, mouthparts yellow, antennz pale yellow, outer 
joint triangular, arista brownish, twice as long as last joint. Thorax shining, scutellum sometimes brown, bristles 
brown, nota! hairs pale and relatively long. Abdomen central dark, pygidium long, asymmetrical, open, the 
central filament consisting of a long strong curved hook, with black point, the right valve ending above in a long 
