300 HYMENOPTERA OF AMERICA. [PART I. 



the segment slightly swelled into two little cheeks before the 

 channel ; the edge strongly reflexed ; the edge of the 3d also a 

 little reflexed; the 2d beneath as tuberculate at base. The 

 whole insect finely and densely punctured, on the abdomen as 

 well as on the thorax; more coarsely on the margin of 2-4 seg- 

 ments. The body woolly, furnished with gray-fulvous hair. 



Black. Mandibles, the 2-3 first joints of antennae, a frontal 

 udinal line, an elongate large post-ocular spot, not touching 

 the eyes, and an angulate line on the vertex parted by the 

 tubercle, and continuing along the inner orbits of the eyes, 

 rufous. Prothorax, tegulae, a spot under the wing, post-scutel, 

 hinder part of scutel, and often the angles of metathorax, rufous. 

 Abdomen rufous; the base of the first two segments black, and 

 the margin of all segments yellowish. The black of the base is 

 often prolonged on the middle of the segment. Feet rufous. 

 Wings smoky, with the anterior edge ferruginous. 



% . Clypeus wider than long, fulvous or yellowish, with argen- 

 teous reflections, although having some black hair; its inferior 

 margin rounded, with a little notch and bidentate in the middle. 

 Hook of the antennas large, arcuate, black 



Var. a. The head not much variegated with ferruginous. 

 Orbits and vertex nearly black. A black spot near the edge of 

 the 2d abd. segment. 



b. Metathorax black. 



Bess. <i. diff. — The coloring'of this insect is what I should like 

 to call the Mexican livery; this dull ferruginous fulvo-velutinous 

 livery being quite a Mexican type. This coloration is quite that 

 of Ancislrocerus tuberculiceps, and much also that of Odynerus 

 Guerreri. From this it differs, by its abdomen, not conical, the 

 first segment being much narrower than the 2d ; by the margin 

 of the 1st segment which is hemmed, and that of the second, much 

 more canaliculate ; by its post-scutel not sharp nor crcnulate, and 

 by its very large, wide clypeus. 



This is quite an exceptional type by the form of its abdomen, 

 post-scutel, and its wide % clypeus. 



Hub. The temperate parts of Mexico. I caught two males in 

 the fine valley of Mextitlan. 



