AMERICAN HYMENOPTERA. 117 



punctures. Median tubercle of the vertex rather large, shining. 

 Third antennal joint somewhat longer than the fourth; apical joint 

 much longer than the preceeding one, rather acute. Pronotum rather 

 strongly carinated; mesonotum rather closely punctured, depressed 

 in the middle anteriorly; mesopleurae shining, with large, rather close 

 punctures. Scutellum punctured like the dorsulum, strongly carinated, 

 as is also the postscutellum. Squamae broad at base, apex acute and 

 curved inwardly; postscutellum between them yellow. Spine short, 

 stout, truncate at apex, broader at base gradually tapering to the 

 apex. Metanotum with strong oblique striae between which are fine, 

 close punctures; metapleura? punctured, with some transverse striae 

 basally. Posterior face finely closely punctured, sharply defined 

 laterally by carinas; fovea V-shaped and strong. Legs stout; tibiae 

 strongly spined. First dorsal abdominal with a distinct median notch; 

 abdomen dorsally punctured like dorsulum; ventrally similarly punc- 

 tured except along the apical margins of the segments which are shining 

 and impunctate. Pygidium well defined, rounded at the apex. Color 

 black; antennas and tarsi somewhat brownish; apical abdominal seg- 

 ment and anterior third of dorsulum red, tegulas a little lighter red; 

 tubercles, lateral spots on 'abdominal segments 1 to 4, those on the 

 first round, creamy-white. Face with silvery hair; thorax with short 

 gray hair. Wings hyaline, very faintly yellowish, slightly iridescent 

 venation dark brown. 



Habitat. — Boulder, Colorado, September 10, 1908 (S. A. 

 Rohwer), at flowers of Polygonum sp. 



This is the largest Oxybelid I have ever seen. It is related 

 to 0. cornutus var. quadricolor Ckll. and Baker, but the spine 

 is shorter, broader, and tapers to a truncate apex. The sides 

 of the metathorax have strias which are not present in quad- 

 ricolor. The markings are whitish as in striatus Baker, but 

 it is very different from that species. 



Oxybelus maimi n. sp. 



Female. — Length 8 mm. Anterior margin of the clypeus as usual; 

 the process prominent. Head below the ocelli closely, rather finely 

 punctured; vertex and occiput with larger, sparser punctures; vertex 

 without a median tubercle. Antennas short and stout, third joint 

 broader at the apex, about the same length as the fourth. Pronotum 

 not strongly carinated, lateral angles not strong. Dorsulum with 

 large separated punctures; mesopleurae shining, with longitudinal 

 striae and punctures. Scutellum shining with but large punctures 

 except on the posterior margin which is rather closely punctured; 

 longitudinal carina evident, but not strong; postscutellum with a 

 rather strong median carina, punctured like the posterior part of the 



TRANS. AM. ENT. SOC, XXXV. MARCH, 1909. 



