PROC. ENT. soc. WASH., VOL. 22, NO. 2, FEB., 1920 37 



Key to Species. 



1. Males 2 



Females 4 



2. Interfrontalia and greater portion of face and parafacials sooty black; 



hypopygium with inferior forceps hatchet-shaped; fifth sternite with 

 two small submedian wartlike elevations which are studded with mi- 

 nute black spines atrifrons, sp. n. 



Interfrontalia entirely reddish; hypopygium with the inferior forceps not 

 hatchet-shaped, slightly dilated or tapered to apices 3 



3. Face blackened on lower half; third antennal joint not twice as long as 



second; inferior hypopygial forceps broadest considerably before apex, 



their tips pointed; fifth sternite as in atrifrons incisurata, sp. n. 



Face entirely pale; third antennal joint over three times as long as second; 

 inferior hypopygial forceps gradually but slightly broadened to apices, 

 truncate at tips; fifth sternite with two long slender submedian pro- 

 cesses which are tapered to apices and furnished with short black set- 

 ulae on their inner or upper surfaces fasciventris, sp. n. 



4. Third antennal joint deep black, not twice as long as second; thorax 



entirely yellow; abdomen yellow, with a narrow glossy black fascia at 



apex of each tergite incisurata, sp. n. 



Third antennal joint obscurely yellowish, largely infuscated, three times 

 as long as second; dorsum of thorax and metanotum as well as some 

 markings on pleura black; abdomen with a narrow fascia on apex of 

 each tergite and the genital segments glossy black . . . .fasciventris, sp. n. 



Gimnomera atrifrons, sp. n. 



Male. Occiput, posterior half of cheeks, upper part of face, and palpi 

 yellow; second antennal joint reddish yellow, remainder of head black. 

 Thorax and abdomen yellowish testaceous, the latter with poorly defined 

 black fasciae at bases of tergites. Legs entirely pale. 



Arista pubescent, very slender except at extreme base. Scutellum with 

 four strong bristles. 



Length 4.25 mm. 



Type. St. Anthony Park, Minn. (Lugger). One male. 



Gimnomera incisurata, sp. n. 



Male. Yellow, third antennal joint, lower half of face, ocellar triangle, 

 and tips of inferior hypopygial forceps black. 



Arista as in preceding species. Other characters as in key. 



