26 U. S. NATIONAL MUSEUM BULLETIN 216 



base; front femur with a broad, shallow excision beneath; the excised 

 region polished except along the posterior margin where it is very 

 finely, longitudinally aciculate; front tibia slightly bent; abdominal 

 tergites unusually slender, extensively polished, and varying consider- 

 ably in density of punctation; tergite 1 elevated along middle beyond 

 basal declivity, and with a broad, oblique impression on either side, in 

 both regions with only a few suberased punctures; tergites 2-7 polished 

 and rather sparsely punctate, with punctures most distinct on tergites 

 2 and 3, rather weak on tergites 4 and 5, and weak to obsolete on ter- 

 gites 6 and 7. 



Head black; scape and pedicel whitish beneath; basal segments of 

 flagellum sordid yellowish beneath; mandible reddish; palpi, tegula, 

 stripe on upper margin of pronotum extending from hind corner to a 

 point opposite origin of notaulus, and a narrow line on mesepimeron, 

 whitish; thorax red with conspicuous black markings, the latter 

 principally as follows — prothorax except narrow submarginal stripe 

 above, spot at middle of mesoscutum, small spot immediately in front 

 of scutellum, postnotum except at middle, large spot in upper posterior 

 corner of mesepisternum, most of prepectus, metapleurum in region 

 above level of propodeal spiracle, metasternum, broad median longi- 

 tudinal stripe on propodeum, and propodeum narrowly at base and 

 apex; front and middle legs with coxae and trochanters very pale 

 yellowish, femora pale reddish above varying to more or less pale 

 yellowish on sides and beneath, and tibiae and tarsi pale yellowish 

 more or less stained with pale reddish; hind coxa and femur except at 

 apex, reddish; hind trochanters, tibia, and tarsus pale yellowish; 

 apices of all tarsi fuscous; abdomen black to somewhat piceous. 



Female: Front wing 8.0 to 8.5 mm. long; antenna with 26 to 28 

 segments; cheek about 0.33 times breadth of mandible at base; thorax 

 and propodeum closely resembling male; abdomen moderately stout; 

 tergite 1 weakly convex, smooth and impunctate except for a very few, 

 shallow or suberased punctures; tergites 2-5 each with a pair of rather 

 prominent, impunctate callosities and a broad, impunctate, apical 

 margin; bases of tergites 2-6 each with a distinct, densely punctate, 

 transverse impression; tergite 7 rather indistinctly punctate; sheath 

 about 0.55 times as long as abdomen. 



Color as in male except as follows — scape pale yellowish at apex 

 beneath; pedicel yellowish to yellowish brown beneath; flagellum 

 pale brown beneath; black on prepectus extending behind prepectal 

 carina as a small spot on mesepisternum; black on metasternum 

 extending to include lower portions of metapleurum; propodeum 

 black with a reddish stripe on either side along the rounded margin of 

 the dorsal surface; abdomen with tergites varying from mostly black 

 to mostly dull reddish, frequently several tergites black with subapical 



