378 Dr. A. S. Packard, Jr's Revision of the 



ovate enclosure, minutely lineated by diverging striatuke, so fine on the 

 convexities that the surface, to the naked eye, seems smooth; posterior 

 vertical face of this segment, flat trapezoidal, mesial furrow shallow, 

 with coarser lines than in the enclosure ; sides limited by a distinct 

 raised line ; flanks finely lineated. Tegulae testaceous, hinder wing 

 pieces yellow, large anterior one black; costal nervures dark, ptero- 

 stigma black, wings clear iridescent. Fore femora yellow beneath in 



% , in o tips only yellow ; two posterior pairs black-brown ; fore tibise 

 entirely yellow, middle stained with brown inside, hind pair black, with 

 a broad yellow ring at base ; fore tarsi yellow, fuscous on the terminal 

 joints, middle and hind yellowish testaceous, basal and terminal joints 

 with an obscure, peculiar light brown tint. Abdomen shaped as usual, 

 cylindrical, shorter than the rest of the body in both sexes, broader in 



9 . Edge of rings not paler than the rest of the segment. Tip of 9 

 unusually broad, nearly equilaterally triangular, surface flat, with a few 

 scattered, short, minute setae, slightly ridged on the setas, not grooved, 

 and twice as broad as in B. impressifrons. 



Length of body, .18; head and thorax together, .11 ; abdomen, .8 

 inch. 



Brunswick, Maine, abundant on flowers in August. (Packard.) 

 Differs from the allied species, not only by its smaller size, but when 

 compared with B. Harrisii the head is seen to be larger, the femora 

 stouter, prothorax narrower, in a longitudinal sense, than in the other 

 species, and from both in the presence of the yellow tubercle. B. im- 

 pressifrons differs from both in the polished, smooth, propodial enclo- 

 sure. The scape of the present species is blacker than in the other spe- 

 cies, and the rings of the abdomen are wholly black, which will readily 

 distinguish it from the smaller species of the genus. It is allied to and 

 represents in this country, Crabro Westmaeli V. Lind., and C. spini- 

 pectus Shuck, of Europe. 



KHOPALUM, Kirby. 



Rhopalum, Kirby, Steph. Syst. Cat. 366. (1829). 



Physocelis, St. Farg., Ann. Ent. Soc. France. (1S34). 



Corynopus, St. Farg., Ann. Ent. Soc. France. (1834). 

 % . Head transversely elliptical, not oblong, as the sides of the 

 head round regularly, since it is very short and broad, and the sides 

 narrow rapidly behind the eyes, being more transverse and shorter (an- 

 tero-posteriorly) than in Blepharipus. Vertex much as in Blepharipus, 

 but not so depressed in front of the ocelli, which are situated in a more 

 equilateral triangle and are more prominent than in Blepharipus. Frontal 

 impressed line deep, well marked, front convex on each side. Eyes 



