Fossorial Ilymcnoptcra of North America. 381 



Tip of fore trochanters, coxa) and fore-legs, yellow, base of femora 

 piceous, hind coxa) yellow. Middle femora brown-black above on the 

 basal two-thirds; tibia) dark at base; hind coxa) and trochanters whit- 

 ish, femora entirely black ; tibiae white at base, fuscous at tip beneath 

 externally, with a few minute spinules ; fore and middle tarsi white, 

 on the tips of the middle joint a narrow rim of dark ; hind tarsi brown, 

 with a large lobular dilatation on the outer side, especially on the basal 

 joint, which is twice broader than the succeeding ones; all the joints 

 are much shorter and stouter than the two anterior pairs of tarsi. 



Abdomen black, extreme tip sub-fuscous, with a minute, slight, thin 

 hirsuties. 



Length of body, .24 ; head and thorax together, .10 ; abdomen, .14 

 inch. 



9 . Head of much the same size and proportions as in B. minimus, 

 but the mesial impressed line is less distinct than usual. Eyes and 

 ocelli much the same, vertex covered more thickly with minute hairs ; 

 antennal groove broad and flat, highly polished ; orbits lined with a 

 fine, sparse, silvery pubescence. In front the head is higher and nar- 

 rower ; the clypeal region narrow, and the clypeus longer and narrower 

 than in any of the other species, being raised, though scarcely carinated, 

 produced into a broad, triangular, acute tooth or lobe, with a minute 

 tooth on each side ; mandibles yellowish testaceous, black at base and 

 tips, tridentate. Antenna) clavate, scape slender, thickening towards 

 end, entirely yellow; flagellum black-brown, joints more swollen than 

 in the other species, terminal joints unusually large, obconic, beneath 

 testaceous on terminal half of joints, sometimes forming obscure testa- 

 ceous rings. 



Thorax entirely black, except the yellow tubercle, minutely punc- 

 tured ; meso-scutellum and meta-scutellum black, punctured like the 

 rest of the thorax. Propodeum smooth and highly polished on the en- 

 closure, which is smaller and less distinct than usual; mesial furrow 

 deep, triangular at bottom, not flat; sides of metathorax ridged. Te- 

 gula) and hinge-pieces yellowish testaceous, wings clear, indistinct, 

 nervures black, ptero-stigma very distinct, black. Femora thickened 

 in the middle, hind pair minutely 4-toothed beneath ; outer half of fore 

 and middle femora yellow, posterior pair slightly tipped with yellow ; 

 two fore pairs of tibia) yellow, posterior yellow at base, brown exter- 

 nally ; tarsi long and slender. 



Abdomen equalling in length the head and thorax together, basal 

 joint long and pedicellate, as long as the abdomen is wide, pyriform, 



