HYMENOPTERA 163 



yellow. The metathorax is incompletely areolated, the areola and the 

 petiole area confluent, the lateral apical areas complete, the basal lateral 

 and the middle lateral areas being represented by a single large area. 



The abdomen varies from black to rufo-piceous, the petiole usually 

 rufous and finely, longitudinally aciculated at apex, about thrice as long 

 as wide ; the body of abdomen viewed from above is oblong-oval or 

 obovate, viewed from beneath it is seen to be compressed at apex ; the 

 whole surface is highly polished, impuncate, segments i to 3 (or 2 to 

 4, counting the petiole as the first) occupying most of the surface, the 

 first the longest segment ; ovipositor exserted but not as long as the 

 basal joint of hind tarsi. 



jSIale. — Length 1.5 to 1.8 mm. Agrees very well with the female 

 except that the antennae are longer, filiform, not thickened toward apex, 

 and always 19-jointed ; the abdomen is clavate, the petiole much longer 

 and black, the body being pear-shaped, the two basal segments and 

 sometimes the third are usually rufous, while the tibiie are embrowned ; 

 palpi yellowish. 



Type. — Cat. No. 5549, U. S. Nat. Museum. From St. Paul Island, 

 August 15 (Fur Seal Commission). Eight specimens. 



XESTOPHYA NIGRIFES sp. nov. 



Male. — Length 2.5 mm. Wholly black, except as follows : An 

 annulus at base of first joint of the flagellum, tibial spurs, sutures be- 

 tween the trochanters and base of femora, the extreme apex of front 

 femora, their tibiie at base and beneath and their tarsi, pale yellowish, 

 rest of legs and the palpi black. Wings hyaline, the stigma and veins 

 light brownish. 



Type. — Cat. No. 5550, U. S. Nat. Museum. From St. Paul Island, 

 August 15 (Fur Seal Commission). One specimen. 



Genus Asynocrita Forster. 

 ASYNOCRITA sp. 

 From Unalaska. A single specimen too badly broken for describing. 



Genus Exolytus Holmgren. 



This genus is probably parasitic upon dipterous larvae and is well 

 represented in all boreal regions, though comparatively few have been 

 described in the North American fauna. There are now known from 

 Alaska eleven species {sens, lat.) which may be recognized by the 

 use of the following table. 



