Fossorial Ilymenoptera of North America. 383 



derer than in 7?. pedkellatum. Abdomen pcdicellated as usual, pedicel 

 deeply grooved on the basal half towards the insertion of the abdomen ; 

 anterior half of the third ring reddish, beneath spreading towards the 

 pedicel; edges of the succeeding segments obscurely testaceous, ex- 

 treme tip rufous, especially beneath. 



Length, .20 inch. 



9 . Head transversely oblong, deeply impressed as usual in front of 

 the ocelli, clypeal region broad, clypeus a little more than one-half as 

 long as broad, square in front; low, carinated, silvery. Mandibles 

 pale-yellowish testaceous; scape entirely yellow, two basal joints of fla- 

 gellum testaceous beneath and at tips, brown above, remaining ones 

 brown. Wings and legs as in % , but middle pair are testaceous. Ab- 

 domen as in % , the tip is not carinated, hirsute, scarcely redder than 

 in % , beneath almost entirely yellow. 



Length, .22 inch. 



Illinois, (Coll. Ent. Soc. Phil.). 



This species may be easily recognized by its small size, the red ring 

 on the anterior half of the 3d abdominal ring, and the red tip; the 

 male, by its acute clypeus, its pubescent propodeum, and the two ante- 

 rior pair of legs being yellow. The 9 differs in the clypeus being 

 square in front, rather resembling Blepharipus in this respect. 



One of the specimens from Illinois has the abdomen black above, 

 and might at first be referred to a different species, but beneath, the 

 band appears, showing an evident transition to the more usual ringed 

 form. 



Desideratum. 

 Crabro (Rhopalum) claviventris, Cress., Proc. iv. p. 151. (1865). 

 Cuba. (Gundlach). 



Subfamily Pemphredonin.e. 



Head subcuboidal and not as long as broad, being transversely oblong, 

 and the sides angulated ; the vertex is broad and flat, at right angles 

 to the front, which bends down suddenly; ocelli placed in an equila- 

 teral triangle in the ceutre of vertex. Eyes oval, of moderate width. 



Front broad, square, narrowing slightly in front, sunken, sometimes 

 with silvery bristles below the antennae ; which are small, geniculate, 

 inserted moderately far apart below the middle of the front, being in- 

 termediate in this respect between Cerceris and Crabro ; the 2d joint 

 is long, and the remaining joints are widely bent at right angles to the 

 2d, they are thick throughout, hardly thickened towards the tips. The 

 clypeal region is lozenge-shaped, being angulated at the base, and so 



