374 AMERICAN HYMENOPTERA. 



pile ; fore and middle tibise dark, but often with a little ferruginous 

 pile on their hind sides near their tips ; corbicular fringes black or 

 more or less strongly ferruginous. 



Worker. — Much like the queen, but the yellow pile on the occiput 

 often with black hairs strongly admixed ; metapleura and sides of me- 

 dian segment always clothed with yellow pile ; the two basal dorsal 

 abdominal segments entirely covered with yellow pile. 



Male. Head. — Face densely covered with a patch of pure yellow 

 pile; occiput with a large triangular patch of yellow pile, connected 

 on each side with the large amount of similar pile sometimes nearly 

 covering the cheek. Malar space distinctly longer than its width at 

 the apex, about one-fourth as long as the eye. Clypeus mostly covered 

 up with yellow pile. Flagellum of antenna about three times as long 

 as the scape; third antennal segment somewhat longer than the fifth, 

 the fifth distinctly longer than the fourth. 



Thorax. — Clothed with yellow pile, except for a narrow and usually 

 poorly defined black interalar band ; this band sometimes almost en- 

 tirely obliterated by yellow hairs. 



Abdo7nefi. — Dorsum : segments one and two entirely yellow ; seg- 

 ments three and four covered with ferruginous pile ; segment five occa- 

 sionally entirely black, but usually largely, and sometimes entirely, 

 covered with ferruginous pile; segments six and seven dark, but very 

 often with some ferruginous hair admixed. Venter mostly clothed 

 with yellow pile. 



Genitalia. — Outer spatha much like that of B. vagans (fig. 131). 

 Inner spatha much like that of vagans (fig. 105), but the hind margin 

 of the apical portion protruding strongly in the middle so as to make 

 the apex appear weakly trilobate. Claspers and sagittse about like 

 those of melanopygus, bimaculatus and fernaldi (figs. 74 and 110), but 

 the tips of the volsell^ narrower and their apical projections less 

 prominent. 



fr?«^^.— Subhyaline, the fore pair darkest in the region beyond the 

 veins. 



Legs. — Coxae, trochanters and femora all with much yellow pile; 

 fore and middle tibiae sometimes entirely dark, but usually with more 

 or less light or ferruginous pile on their hind sides ; hind tibiae with 

 outer faces convex and almost or entirely naked, the fringes dark, yel- 

 low, or somewhat ferruginous ; hind metatarsi usually with moderately 

 long and ferruginous posterior fringes. 



Dimensions. — Length : queen, \2\ mm. to 16 mm. ; worker, 9| mm. 

 to \2\ mm. ; male, 10 mm. to 13 mm. Spread of wings: queen, 29 

 mm. to 33 mm. ; worker, 23 mm. to 28 mm. ; male, 22 mm. to 29 

 mm. Width of abdomen at second segment : queen, 7 mm. to 9 mm. ; 

 worker, 4| mm. to 6^ mm. ; male, \\ mm. to 51 mm. 



Redescribed from many specimens (one a homotype of 

 juxtus Cress.). 



