AMERICAN DIPTERA. , 341 



lum with two moderately long and two short bristles. Abdomen dusted with 

 gray, hypopygium small, black, terminal, not pollinose, upper piece with a close 

 fringe of yellow bristles on the left side. Legs including coxfE pale yellow, tarsi 

 strongly annulate with black, spur of middle tibise prominent, black, front 

 femora nearly as thick as middle ones, fringed beneath with white cilia, middle 

 femora and tibiae with a double series of minute setulse on under surface, front 

 tibisB slightly bowed and incrassate. Halteres whitish. Wings yellowish, veins 

 yellow, anal vein obsolete at base, distance between the two cross-veins on the 

 fourth vein somewhat greater than the length of the first cross-vein, second basal 

 cell the longer, its cross-vein oblique, third and fourth veins parallel. 

 Var. — Ground color of abdomen becoming yellow. 



Numerous specimens, the males predominating. Cloudcroft, New 

 Mexico, May 27, 1902. H. L. Viereck, collector. 



This species will run to crassifemoris in the table on page 215, 

 antea, but is sufficiently differentiated by its pollinose abdomen. 

 Only two other of the previously described species of Platypalpus 

 ' canus and incurvus) have the abdomen pollinose, but as both of 

 the.se have black antennae the present form can be quickly recog- 

 nized. " The following species should also be compared. 



Platypalpus rnfiveiitris sp. nov. 

 Male and Female. Length 2-2.5 mm. — Thorax black, gray dusted, abdomen 

 testaceous, lightly dusted, subshining. Face and front whitish, occiput cinere- 

 ous. Antennte black, short, outer joint short, ovate, pointed, its bristle twice its 

 length. Thoracic notum and abdomen with yellowish tomentum, pleurae cine- 

 reous, the usual shining spot overlaid with pollen also, bristles yellow, scutellum 

 with two moderate bristles. Abdomen lightly dusted, less so in the female, in 

 the male dusky at the base, in the female reddish yellow, hypopygium small, 

 blackish, with a few long yellow hairs extending laterally from the left side. 

 Legs including the coxae yellow, tarsi not annulate, their very tip dusky, spur of 

 middle tibiae black, front tibiae not incrassate, front femora half as thick as the 

 middle ones. Halteres yellow ; wings as in Vierecki. 



One male, seven females; Cloudcroft, New Mexico. June 17, 

 1902. (H. L. Viereck). 



This and the variety of the preceding species are the only North 

 American species of Platypalpus known with black thorax and red 

 abdomen. It can be quickly distinguished from Vierecki by the 

 shape and color of the antennae, and by the uniform tarsal coloration. 



Page 219. Platypalpus lietus Loew. 



The tibial spur is as large as usual for this genus. The apices of 

 the tarsal joints are scarcely darker than the rest. The third and 

 fourth veins gently converge before the tip of the wing and then 

 continue subparallel. 



TRANS. AM. ENT. SOC, XXVIII. SEPTEMBEK, 1902. 



