440 AMERICAN HYMENOPTERA. 



Bombiis hyperboreus vsi.r . A/beriensis Cock&reW, Can. Ent., XLI, Jan., 

 1909, p. 36. 

 " rufocinctus phacelice Cockerell, Can. Ent., XLII, 1910, p. 25. 

 astragali Cockerell, Can. Ent., XLII, 1910, p. 25. 



Types. — In the collection of the American Entomological 

 Society. 



Pile short ; malar space short ; face usually dark ; occiput yellow ; 

 legs of females dark ; wings not very dark ; color characters extremely 

 variable — abdomen ferruginous and yellow, black and yellow , or black, 

 ferruginous and yellow ; dorsum, of thorax m,ostly yellow, but at least 

 the disc dark. 



Queen. Head. — Broadly rounded trapeziform ; face mostly black, 

 but with a sprinkling of light pile between and above the bases of the 

 antennae (not very noticeable, in most cases, except with the aid of a 

 lens) ; occiput yellow, but often with a more or less strong admixture 

 of dark hairs; sides of head black. Labrum with tubercle-like areas 

 well separated and with rounded margins and fiat summits ; shelf-like 

 projection rather small and narrow ; translucent areas faintly visible 

 to the naked eye. Malar space considerably shorter than its width at 

 the apex, not more than one-sixth as long as the eye. Clypeus rather 

 sparsely and delicately punctate. Ocelli not far below the supra- 

 orbital line, slightly above the narrowest part of the vertex. Flagel- 

 lum of antennae about one and two-thirds times as long as scape ; 

 third antennal segment equal to the fourth and fifth taken together, 

 the fifth scarcely longer than the fourth. 



Thorax. — Dorsum sometimes with only the disc black and some- 

 times with a black interalar band, the remainder being covered 

 with yellow pile ; center of disc naked, smooth and shining. Meso- 

 pleura usually covered for the most part with yellow pile, often en- 

 tirely so to the bases of the legs, but as often with the very lowest 

 parts black, and occasionally as much as the entire lower halves dark. 

 Metapleura and sides of median segment sometimes entirely dark, 

 sometimes with mixed yellow and black pile and sometimes with yel- 

 low pile only. 



Abdom.en. — Dorsum : segment one yellow ; segment two with basal 

 middle yellow, the rest black ; segment three black ; segment four 

 with basal portion black and apical portion covered with yellow pile ; 

 segment five with considerable yellow pile on the sides, but black in 

 the middle; segment six black. Venter mostly black, but often with 

 a considerable sprinkling of light hairs on the apical margins of some 

 of the segments, especially toward the sides. Epipygium with a low, 

 rounded, longitudinal, median carina on its apical portion. Hypo- 

 pygium tending to be carinate on apical portion. 



Wings. — Not very deeply stained with brown ; the fore pair gener- 

 ally lighter across the middle portion. 



