OF WASHINGTON, VOLUME XVIII, 1916 107 



Chrysogaster nigripes Loew. 



Rather small, dark species. The apical cross vein is bent inward 

 to join the third vein. Stigma much longer than the distance from the 

 tip of the second vein to tip of the third. Legs entirely black. 



Male: Ocellar triangle raised and with rather short black pile. Frons 

 but little inflated, shining bluish-greenish black, the pile black, longer 

 than on the ocellar triangle. Antennae quite small, third joint ovate, 

 yellowish brown, the arista darker. Below the antennae a transverse 

 whitish pollinose band extends to the eyes. Face colored as the frons, 

 with a small tubercle. Thorax velvet black with numerous irregular me- 

 tallic greenish spots enclosing punctures, more or less confluent at the 

 sides, and a pair of rather ill-defined stripes of the same color on the 

 dorsum midway of the middle and the sides; pile short and rather dense, 

 blackish. Scutellum concolorous with mesonotal punctures. Dorsum of 

 abdomen opaque, the sides shining, dark metallic green. Wings with a 

 distinct blackish tinge. Squamae and halteres darkened. Length: about 

 6 mm.; wing about 4.5 mm. 



Female: More bluish or greenish than the males, immature specimens 

 purplish. The pile everywhere shorter, being hardly noticeable. Frons 

 transversely rugose, interrupted at the middle by a longitudinal ridge, 

 above the antennae smoothed, with depression in the middle and some- 

 what produced forward. The eye margins but little wider below than at 

 vertex. Antennae noticeably larger than in the male, yellow, somewhat 

 darkened. Below the antennae a whitish, pollinose band extends across 

 to the eyes. Mesonotum and scutellum dark metallic blue, unspotted and 

 without stripes. Wings a little clearer, in immature specimens hyaline, 

 and the squamae paler than in the male. Length: about 5.5 mm.; wing 

 about 4.5 mm. 



Specimens from Ontario, Maine, New Hampshire, Massachu- 

 setts, Connecticut, New York, Maryland, Virginia, North Caro-. 

 lina, Georgia. 



Chrysogaster inflatifrons, new species. 



Large species, color dark greenish black. The apical cross vein not 

 recurrent, stigma much longer than the distance between the tips of the 

 third and fourth vein. Legs entirely black. 



Male: Ocellar triangle prominent, with black pile. The frons well 

 puffed out, shining, with rather long, black hairs. Antennae reddish yel- 

 low, the arista blackish; third joint ovate, nearly as broad as long. Be- 

 low the antennae a whitish pollinose band extends across to the eyes. 

 Face with large rugulose spots on the sides above and with a small tubercle. 

 Mesonotum velvety black and with many punctures which are enclosed by 

 metallic greenish spots and with dense, short, blackish pile; scutellum 

 unicolorous with the spots on thorax. Dorsum of abdomen subopaque, 



