Fossorial JTymcnoptcra of North America. 81 



From C. 10-maculatus, to which the present species is nearest allied, 

 it differs in being larger, in its longer clypeus, narrower prothorax, in 

 wanting the oblong spot behind the tubercle, in having almost entirely 

 rufous femora, where in 0. lQ-macuIatus they are more than half black 

 and broadly tipped with yellow; in having small less contiguous abdo- 

 minal fascia? and in the basal joint being broadly rufous. My specimen 

 is evidently immature, as the fasciae of abdomen are very obscure, and 

 Smith does not notice the rufous tinge pervading the yellow fasciae. 



Crabro cubensis, Cresson. 



C. cubensis, Cresson, Proc. iv. p. 152. (1865.) 

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



Group C. 

 Crabro mfifemur, n. sp. 



% . Head cubical, a little more than twice as long as broad, but 

 slightly narrowing behind, above very convex, ocelli arranged in a low 

 but nearly equilateral triangle, slightly hirsute on each side in front of 

 the ocelli, graduating into the silvery pile broadly lining the orbits; 

 sides of head converge sensibly towards the clypeal region which is 

 covered with a silvery pubescence. That on the clypeus itself is dull 

 yellowish ; clypeus itself two-thirds as long as broad, obscurely cari- 

 nated. Mandibles yellow, becoming ferruginous and then black at tips. 

 Antennae short and thick, scape much thickened just before the middle, 

 entirely yellow, fifth joint of the flagellum much pinched in beneath, 

 giving a bidentate appearance, basal and third joints of antennae ferru- 

 ginous, remaining joints blackish. 



Head and body narrow, coarsely punctured, black. Prothorax on 

 each side transversely cariuated, acutely angled on the sides, yellow 

 above. Surface of thorax behind very convex; on mesoscutellum no 

 lines orsubmesial ridges, or parapsidal grooves present; scutellum large, 

 black, a yellow spot on the smooth postscutellum. Propodeum with the 

 enclosure not very distinct, punctostriated obliquely, with a well 

 marked mesial furrow, especially wide and deep posteriorly. Tegulae 

 testaceous; wing pieces yellow, ferruginous and black; nervules black- 

 ish, more ferruginous at base, wincrs a little clouded. Below the inser- 

 tion of the wings the flanks are covered with a thin silvery pile; yellow 

 tubercle very distinct. Femora above slightly yellow, honey yellow 

 towards tips, beneath black ; tibiae yellow, ferruginous within ; tarsal 

 joints yellow, slightly ferruginous at tip ; unguinal joint brown-black. 



Abdomen high narrow, very convex above, flattened beneath; each 

 ring convex mesially, edges slightly emarginate, shorter than head and 



PROCEEDINGS EXT. SOC. PHILAD. MAY, 1866. 



