MOUNTAIN ANTS OF NORTH AMERICA. 529 



corners of the head, fuiiicuH scarcely enhirgcd at their tips; joints 

 2-3 as broad as long, all the other joints distinctly longer than broad, 

 the ninth and tenth being nearly 1^ times as long as broad. Clypeus 

 very bluntly subcarinate. Frontal area large, triangular. Palpi 

 rather long, the six joints of the maxillary pair gradually decreasing 

 in length towards the tip as in other members of the subgenus. Thorax 

 rather short, the pro- and mesonotum together as long as the epino- 

 tum; mesonotum as long as broad, the promesonotal suture not deeply 

 impressed; mesoepinotal constriction short but moderately deep; 

 epinotum in profile Avith the con\'ex base about j as long as the flat, 

 sloping declivity. Petiole narrow and rather high, much compressed 

 anteroposteriorly, with flat anterior and posterior surfaces, straight, 

 nearly subparallel sides and rather sharp, entire and evenly rounded 

 superior border. Gaster broad, flattened dorsoventrally. 



Surface shining; mandibles finely striated; remainder of body very 

 finely and superficially shagreened. 



Pubescence and hairs pale yellow, the former appressed, abundant 

 and moderately long on the body and appendages, the latter blunt 

 and erect, very sparse on the head, more numerous on the thoracic 

 dorsum and still more abundant on the gaster. 



Pale yellow; head and antennae a little darker; mandibles with 

 reddish borders and teeth. 



Female. Length 3.5 mm. 



Head subrectangular, slightly broader than long, with rather deeply 

 and broadly excised posterior border and straight cheeks. Eyes large, 

 convex, more than half as long as the cheeks. Antennal scapes sur- 

 passing the posterior corners of the head by about \ their length; 

 all the funicular joints distinctly longer than broad. Thorax not 

 broader through the wing-insertions than the head through the eyes, 

 flattened above; mesonotum nearly as long as broad. Petiole with 

 more convex sides and blunter superior border than in the worker, 

 this border feebly emarginate in the middle in some specimens. Wings 

 rather long. 



Sculpture and pubescence much as in the worker, erect hairs on the 

 thorax and gaster apparently less numerous and conspicuous. 



Color like that of the worker, but the occipital portion of the head, 

 the pro- and mesonotum, scutellum and dorsal surface of the gaster 

 pale brown. Wings grayish, not infuscated at their bases, with pale 

 brown veins and stigma. 



Described from nine workers and three females "taken by Dr, W. M. 

 Mann at Pyramid Lake, Nevada. 



