42 PROCEEDINGS OF THE NATIONAL MUSEUM vol 82 



The general rule is that the eps 2 is rather coarsely longitudinally 

 striate and the upper edge of eps 1 has some faint striae, while be- 

 low the surface is alutaceous and furnished with scattered shallow 

 punctures, but sometimes there are more conspicuous longitudinal 

 striae on the upper half or so of eps 1, and in one male I find even 

 vertical rugae on the upper third. I do not care to accept these speci- 

 mens as entitled to separation from pauper on the material available, 

 but should the characters be met with in series of specimens, it 

 would be well to consider them as distinct species. 



Length, 6-7.6 mm. 



Originally described from Illinois and recorded from New Jersey. 

 Before me there are specimens from Salisbury Cove, Maine; near 

 Bennings, D.C. ; Bladensburg, Md. ; Falls Church, Turkey Run, and 

 Hunter, Va.; Nelson and Nerepis, N.H. ; Chicago, 111,; Ithaca, N.Y. ; 

 Massachusetts; and Canada, the last two without more definite 

 localities. July to October. 



PSEN (MEflESA) GREGARIUS Fox 



Paen gregarius Fox, Trans. Ainer. Ent. Soc, vol. 25, p. 16, 1898. (Male.) 



Fox in his original description stated that this species is very 

 similar to unicinctus, in which I concur. He distinguished gregaritis 

 mainly on the shorter and more clavate antennal flagellum and the 

 coarser propodeal rugae. The exceptionally narrow second sub- 

 marginal cell which he found in his type specimen is not characteris- 

 tic of the species, a fact that he suspected might be the case. He did 

 not note the differently colored underside of the antennal flagellum 

 in the two species, which I use for the separation of unicinctus and 

 another species from the remainder of this group. 



The antennal flagellum in typical males has segments 2 to 5 with a 

 rounded elevation on one side, which is highest at middle, but there 

 are many specimens that do not have this elevation and possibly 

 these should be separated as a distinct species. I do not care to go 

 this far, so accept these as a variety, which is briefly distinguished 

 below. 



Length, 6.5-8 mm. 



Originally described from Colorado. I have before me 1 male and 

 1 female from the same State, without other data (Baker collection). 



PSEN (MIMESA) GREGARIUS SIMPLEX, new variety 



Male and female. — Similar to the typical form in coloration, dif- 

 fering essentially in lacking sensory elevations on the antennal fla- 

 gellum. The striae on the lateral areas of propodeum contiguous 

 with the enclosure are very fine and diverge obliquely outward and 

 slightly backward. 



Length, 7-8 mm. 



