HENRY J. FRANKLIN. 383 



those of most Botnbus species ; hind metatarsi bearing only short 

 spines and pubescence, except for a posterior basal fringe of short 

 hairs and a scattering of hairs of about the same length on the basal 

 portion of their outer sides, 



Worker. — Much like the queen, but with no distinct black interalar 

 band present ; pile of dorsal apical segments of abdomen, as a rule, 

 much more distinctly ferruginous ; second segment, on a good share 

 of the specimens, entirely yellow ; basal part of fourth segment often 

 bearing black pile; wings somewhat lighter than those of queen, 

 scarcely tinged at all with brown ; fore and middle tibiae and cor- 

 bicular fringes usually black ; tarsi not especially reddish. 



Male. Head. — Shaped and colored much like that of queen and 

 worker, but, in the majority of specimens, with pile of face and occiput 

 pure yellow — in some, however, with a strong admixture of black 

 hairs ; sides of head behind eyes with a large amount of yellow pile, 

 this connecting with the yellow on the occiput. Labrum transversely 

 concaved in front ; malar space hardly one-fourth as long as eye ; 

 cljrpeus mostly covered up with pile. Flagellum of antennae (fig. 19) 

 about three times as long as scape, somewhat suddenly thickened at 

 base and tapering toward apex ; basal segments with prominent tufts 

 of hair on outer side, these tufts also present on apical segments, but 

 with hairs so short as not to be very noticeable ; third and fifth antennal 

 segments subequal in length, fourth shorter than either. 



Thorax. — Coloration of pile about as in worker, but many speci- 

 mens with anterior part of dorsum pure yellow ; black interalar band 

 very indefinite. 



Abdomen. — Dorsum : first two segments entirely covered with yel- 

 low pile ; third segment entirely black ; fourth segment usually with 

 basal portion black and apical portion ferruginous, in some specimens 

 entirely ferruginous; fifth, sixth and seventh segments ferruginous, 

 sometimes some black hair on the apical segment. Venter clothed with 

 long yellow pile. 



Genitalia. — Outer spatha variable, usually like that of B. vagans 

 (fig. 131). Inner spatha shaped much like that of B. fervidus (fig. 

 101) and sometimes with small fenestras. Claspers (figs. 108 and 109) 

 with branches rather narrow and squarely rounded at the tip as seen 

 from dorsal side ; volsellae appearing truncate at tip and with rounded 

 apical projections; squamae rounded triangular, with pointed tips; 

 sagittse with nearly straight shafts. 



Wings. — About as in worker. 



Legs. — Coxae, trochanters and femora bearing a considerable amount 

 of yellow pile. Fore and middle tibiae and corbicular fringes varying 

 from almost entirely black to somewhat strongly ferruginous mixed 

 with black. Outer faces of posterior tibiae convex and considerably 

 bare ; fringes long and forming distinct corbiculae. Posterior meta- 



TRANS. AM. ENT. SOC, XXX VHI. 



