OF WASHINGTON, VOLUME XVIII, 1916 103 



12. Entire abdomen unicolorous with thorax and as distinctly punctured. 



unicolor n. sp. 

 Disc of abdomen subopaque sinuosa Bigot. 



13. Stigma only about as long as distance between the tips of second and 



third veins; frons in the female with nearly parallel sides and with 

 two slightly rugulose, longitudinal stripes; antennae small; squamae 

 and halteres pale; disc of abdomen shining. (Group 3). . .lata Lw., 9 

 The stigma elongate, much longer than the distance between the tips 

 of the second and third veins; the penultimate section of the fifth 

 vein a little bowed downwards; a transverse whitish pollinose band 

 just below the antennae; antennae very small; disc of abdomen 

 subopaque. (Group 4) 14 



14. Frons in the male but little inflated; in the female the width of the 



eyes at mouth margin but little greater than at vertex; both sexes 



with rather faint vittae on mesonotum; small species. . . .nigripes Lw. 



Thorax without vittae; frons of the males much puffed out; larger 



species 15 



15. Squamae with a darkened tinge; pile on the frons rather long. 



inflatifrons n. sp. 

 Squamae whitish; pile on the frons in male rather short. . texana n. sp. 



Chrysogaster stigmata Will. 



The description of this species was based upon specimens from 

 California. Three specimens, two males and one female, from 

 Moscow, Idaho, sent by Professor Aldrich, agree with the types 

 except that they are somewhat blacker in color, but this is not a 

 sufficient difference to separate them. The antennae of the fe- 

 male are less elongate, the third joint being only a little more 

 than one and a half times as long as broad; the third joint dif- 

 fers further from that of the male in being broadly reddish on 

 the lower margin. 



Chrysogaster robusta, new species. 



A rather large, robust species for this genus; dark greenish bronze. 



Male: Ocellar triangle and frons bronzy green, with conspicuous, 

 pale brownish pile. Antennae blackish, reddish on under side of third 

 joint, which is a little longer than broad; arista dark, very minutely 

 pubescent and but little longer than antennae. Face greenish black, 

 with short white pile, rather gently excavated, mouth margin reaching 

 forward as far as antennal prominence; a distinct whitish pollinose band 

 extending across to the eyes and below this the face is broadly, faintly 

 rugulose. Thorax with very short, pale brownish pile; mesonotum with 

 two median, very faint stripes. Disc of abdomen subopaque, shining 

 at the sides. Hypopygium rather large, with abundant, short, whitish pile. 

 Wings slightly smoky. Squamae whitish and halteres yellowish. The first 



