﻿CAMERON, DIPLOPTERYGA FROM THE SOUTHWEST 79 



segment narrowed at the base, distinctly longer than it is wide at the apex, 

 which is flat. 



Belongs to Saussure's Section I. It comes near A. trichionotiis Cum., but 

 is more slenderly built, is not so densely pilose, and the mark on the clypeus 

 of trichionotus is much larger, triangular, and united by a narrow line to the 

 apex ; the thorax in the latter, too, is wider compared with the length. 



Odynerus approxiniatiis Cam. 

 This species comes close to O. mcdiatns Cam. from California. The fe- 

 males may be separated thus : 



A. Clypeus longer than wide, a broad black mark down the center, com- 

 mencing behind the middle and continued to the apex, the yellow mark 

 on postscutellum rounded at apex, the oblique line on first abdominal 

 segment longish, of equal width, the second abdominal segment fully 

 as long as wide. upproximatus. 



AA. Clypeus as wide as long, the center only marked with black, the yellow 

 mark on postscutellum completely transverse at apex, the oblique line on 

 first abdominal segment broad, narrowed on inner side, the second ab- 

 dominal segment longer than wide. mediatus. 



Odynerus niacfarlandi sp. nov. 



Black, a curved band slightly wider than the antennal scape on the top 

 of the clypeus, small irregular spot on the front, one on the base of the 

 mandibles, a small spot on the top of the outer orbits, a line on the basal fourth 

 of the pronotum, a conical mark below the tegulae a little longer than wide, 

 the entire postscutellum, a line on the sides of the metanotum, its spines, lines 

 on the basal five abdominal segments at the apices, a semi-circular large mark 

 on the sixth, and the apices of the second to fourth ventral segments, yellow. 

 The apices of the femora narrowly and the tibiae yellow ; the base and apex 

 of the hind tibiae and the tarsi rufo-fulvous. Wings hyaline, iridescent, darker 

 colored in front, the radial cellule violaceous, the stigma dark fuscous, the 

 nervures black. Tegulae pale yellow, with the usual fuscous spot. Female, 

 length 8 mm. Sapello Cafion, New Mexico, (Oslar). 



Closely strongly punctured, sparsely pilose, the metapleurae closely weakly 

 obliquely striated. Clypeus pyriform, longer than wide, its apex with a dis- 

 tinct but not deep rounded incision. Temples broad, rounded, nearly as long 

 as the top of the eyes. Thorax more than twice longer than wide, the base 

 transverse, not projecting laterally ; the apex with the sides bluntly rounded, 

 the center very little depressed, the lateral keels large, curved, more prominent 

 than usual. Postscutellum gradually obliquely narrowed to a bluntly rounded 

 point. First abdominal segment, longish, cup-shaped, longer than it is wide 

 at the apex, the base narrowed to a point. Second segment clearly longer than 

 wide, narrowed at the base, the apex more strongly punctured than the rest, 

 with a narrow smooth border. 



A narrow slender species, showing an approach to Nortonia. It is not 

 unlike O. acantlwpus Cam., and has, like that species, a blunt tooth on the toji 



