16 PROCEEDINGS OF THE NATIONAL MUSEUM tol. 82 



punctate on disk. Abdominal petiole longer than hind femur, 

 almost rounded, and bare above, carinate on each side below and 

 with a series of fine hairs mesad of each edge. Only the fourth 

 sternite fasciculate, the hairs much shorter and occupying a much 

 smaller proportion of the width of the apex than in the other species 

 except myersiana. Hind tibia without dorsal spines. Second cubital 

 cell receiving both recurrent nervures. 



Length, 10 mm. 



Type.— VS. '^M. No. 44209, from Beulah, N.Mex., August 8, 1900 

 (T.D. A. and W. P. Cockerell). 



Two male specimens. 



MiMUMESA, new subgenus 



This subgenus is distinguished from the others by the following 

 group of characters, though it is rarely the case that all of them will 

 apply to one species : A well-defined raised line between the antennal 

 insertions extending from anterior ocellus to below level of antennae 

 and usually at the latter point connected with a small tubercle from 

 which extends on each side a slightly raised line laterally ; petiole of 

 abdomen normally very distinctly grooved, one groove on each side 

 of the dorsum, which widen out behind so that the raised central 

 part tapers to a point behind, and the latter is usually more or less 

 noticeably sulcate basally ; clypeus sometimes with two central teeth, 

 which are quite closely placed and rounded, rarely with a much 

 smaller tooth on each side of these; the small upper part of the 

 mesopleura (eps 2) glossy, well distinguished from the large lower 

 part by an impressed line (episternauli), and with at most very 

 fine indistinct punctures, never striate or striato-punctate ; abdomen 

 usually entirely black, red at base in clypeatus. 



Below is given a synoptic key to the species available and under 

 each of the old species recorded in the text are given notes on the 

 examination of the types. 



Subgenotype, Psen niger Packard. 



KEY TO THE SPECIES OF SUBGENUS MIMUMESA 



1. Face with dense decumbent golden pile in female, silvery white haired in 

 male ; antennal flagellum rufous above and below on a little more than 

 its basal third, black beyond ; pygidial area narrow, almost parallel sided, 

 about three times as long as its width at upper extremities of the lateral 

 ridges, surface shining, with a series of large piliferous punctures along 

 each side of basal half ; legs black, tibiae and tarsi orange-yellow. 



johnsoni (Viereck) 



Face with white or silvery pile in both sexes ; antennal flagelUim not yellow 



at base and black at apex 2 



