148 KANSAS UNIVERSISY QUARTERLY. 



I see no reason why calccata should not find place in riatypcza as 

 it seems to diverge from the species of that genus only in the struc- 

 ture of the masculine hind tarsi. The female is purely typical of 

 Platypeza. 



The purpose of the elaborate tarsi of Platypeza oniatipes and P. 

 calceata is doubtless one of adornment. 



Platypeza velutina Loew. — PI. 12, fig. 8. 



Male. Velvety black. Head black; antennae concolorous; face 

 except in middle, and cheeks with black pile. Thorax black, opaque, 

 in some lights more fuscous-black. Abdomsn velvety-black, last 

 segment and very narrowly on the incisures, obscurely cinereous; 

 sides with long black pile. Legs black, sometimes more fuscous, 

 knees a little brownish; of the hind tarsal joints the metatarsus is 

 broadest, the third joint longest. Halteres black. Wings with a 

 very slight yellowish tinge, veins black; posterior crossvein very near 

 border of wing; first basal cell a little shorter than second costal cell; 

 second posterior cell rather long. 



Length 2)^ to 3)^ mm. 



Five specimens. Hop Canyon, Magdalena Mts., N. M., 7,500-8,000 

 feet, August; and one specimen from Beverly, Mass., August 27th, '6S^ 

 all males. I see no appreciable difference between the eastern speci- 

 men and the western ones. 



The above description differs from Loew's in that in the latter the 

 abdomen is "immaculatum" and the wings are "purissime hyaline." 

 It is probable that the first is a sexual difference. Loew described a 

 female. 



Platypeza urabrosa n. sp. — PL 12, fig. 1. 



Male. Black, cinereous. Head cinereous; antennae black with 

 slight hoary pubescence; proboscis pallid; occiput black, opaque. 

 Thorax cinereo-fuscous-black, along the median line with a narrow 

 lighter stripe. Abdomen velvety black; hind border of first segment, 

 two large lateral spots of second and all of sixth except the anterior 

 margin, cinereous. Pile of abdomen long, glistening, yellowish, 

 darker posteriorly, thickest near base on sides; pile of sixth seg- 

 ment more bristle-like, black on sides and reddish on end of segment; 

 often this bristle-like, dark pile begins on fifth segment. Legs sub- 

 lutescent; femora fuscous except at immediate base and tip; last two 

 or three tarsal joints and hind tibire infuscate; hind metatarsi longer 

 and wider^than following joints (PI. 12, fig. 7. — the femur is fore- 

 shortened in the drawing). Halteres yellowish. Wings broad, 

 slightly incinereate; second costal cell very long and broad, about 

 twice as long as first basal cell; posterior crossvein removed from 

 border of wing (on fifth vein) by a distance distinctly greater than 



