216 HYMENOPTEEA. 



and hind wings is much larger, and there is at the apex of both a blackish-violaceous 

 border; the median segment is longer, more narrowed towards the apex, and is 

 neither toothed at the base nor at the apex, the apex having a gradually rounded slope 

 (in P. optima it is abrupt, almost oblique). 



The clypeus is moderately convex, the curve at the apex very slight ; the labrum 

 punctured. The scape of the antennae is dull purplish-pruinose and without hair ; the 

 base of the third joint is black. The head and thorax are velvety, moderately covered 

 with long black hair ; the median segment is densely pilose. The head and thorax 

 have a much more distinct bluish tinge than they have in P. optima, as have also the 

 legs and abdomen. The latter has the apex densely covered with long, black, bristle- 

 like hairs above and beneath, and the other ventral segments have some long hairs. 

 The legs are blue, the spines black. The third transverse cubital nervure is curved 

 (not elbowed as in P. optima), the third cubital cellule being not much narrower at 

 the top than at the bottom ; the first recurrent nervure is received nearer the middle 

 of the cellule than it is in P. optima. 



v' 3. Pepsis guatemalensis. (Tab. xil. fig. 2.) 



Long. 24 millim. $ . 



Hab. Guatemala, San Geronimo (Champion). 



Very similar to P. azteca, but much smaller and more slenderly built ; the body of 

 a more decided violaceous tint ; the cloud at the base of the wings smaller and the 

 one at the apex larger, it extending to the third transverse cubital nervure ; the cubital 

 cellule at the top only half of the width at the bottom ; the third transverse cubital 

 nervure curving more towards the second and thus narrowing the cellule ; the median 

 segment at the base and apex very distinctly toothed, and with the apical transverse 

 ridge more distinct ; the third antennal joint entirely black ; and the apex of the 

 clypeus much more distinctly incised. The head is not much narrowed behind the eyes 

 and is very sparsely covered with black hairs ; the mesonotum has few hairs, and the 

 median segment hardly any, this being another point in which P. guatemalensis differs 

 from P. azteca. The median segment is transversely striolate, and without a central 

 furrow. The apex of the abdomen with long, black, bristle-like hair ; the other segments 

 sparsely haired. The legs have the spines short and black, the legs themselves being 

 purplish-blue. 



A male, also from San Geronimo, apparently belongs to the same species. It agrees 

 with the female in colour and clothing; but the wings are of a duller tint, and only the 

 basal two joints of the antennas are black, the incision in the apex of the clypeus is 

 deeper, the median segment is not so strongly tuberculate, the third cubital cellule is 

 wider at the top, the apex of the abdomen above is covered with black hair, and the 

 ventral surface is sparsely pilose, without tufts. 



