March, 1914.] WhEELER: AnTS FROM HlDALGO^ MeXICO. 45 



of the clypeus and anterior % of head above, except the flattened areas for the 

 scapes, longitudinally rugose. Epinotum and pleurae obscurely rugulose ; sides 

 of epinotum and sides and ventral surface of petiole densely punctate. Re- 

 mainder of thorax and gaster with minute, sparse, piligerous punctures. 



Hairs coarse, yellow, moderately long, suberect on the body, shorter and 

 subappressed on the scapes and legs. 



Brownish yellow ; borders of mandibles, clypeus, gaster, except its base 

 and tip, and head, except the cheeks and posterior corners, brown. In some 

 specimens the upper surface of the thorax also is infuscated. 



Worker. — Length 1.5-2 mm. 



Head subrectangular, excluding the mandibles as broad as long, with the 

 posterior border feebly excised in the middle. Eyes just in front of the median 

 transverse diameter of the head. Mandibles with about 5 denticles. Antennal 

 scapes reaching the posterior border of the head. Clypeus convex, its anterior 

 border rounded and entire. Thorax like that of the soldier, but the pro- and 

 mesonotum less robust, less convex and more evenly rounded in profile and the 

 epinotal spines smaller. Petiole with entire, rather conical node ; postpetiole a 

 little broader than long, broader behind than in front, its sides not angulate. 



Head thorax and pedicel covered with small, dense punctures and the 

 front of the head also delicately longitudinally rugulose so that it is subopaque. 

 The thorax and pericel, too, are subopaque, except the upper surface of the 

 pronotum and the nodes which are more or less shining. 



Pilosity much as in the soldier. 



Color brownish yellow, dorsal surface of the head, thorax and gaster 

 often a little darker. 



Female. — Length 4.5-5 mm. 



Head subrectangular, as broad as long, a little broader behind than in 

 front, the posterior border nearly straight. Thorax seen from above elliptical, 

 but narrowed in the epinotal region, which is sloping in profile, with stout, 

 short, pointed teeth. Petiolar node emarginate. Postpetiole nearly twice as 

 broad as long, its sides in the middle produced as blunt conules. Gaster 

 broadly elliptical. Wings very long (7.5 mm.). 



Mandibles rather shining, coarsely striato-punctate ; clypeus and head sub- 

 opaque, longitudinally rugose and reticulate even on the depressions for the 

 antennal scapes. Pronotum opaque and rugulose. Remainder of thorax shin- 

 ing, but with the sides and dorsal surface coarsely punctate and striate. Petiole 

 and postpetiole less shining than the gaster, with coarse piligerous punctures. 

 Gaster sparsely and minutely punctate, with large punctures on the extreme 

 base of the first segment. 



Hairs longer and more abundant than in the soldier. 



Dark piceous brown or black; mandibles, except their borders, clypeus, 

 cheeks, legs and bases and tips of antennal funiculi brownish yellow, the 

 middle portions of the tibiae and femora darker. Wings gray, with pale 

 brown veins and stigma. 



Described from numerous specimens taken from many colonies of 



