350 ANNALS NEW YORK ACADEMY OF SCIENCES 



as broad, about one-half as broad behind as in front ; its anterior border 

 broadly rounded and entire, its lateral and posterior borders also rounded, the 

 former diverging anteriorly. A raised, longitudinal line, most distinct on the 

 posterior portion of the clypeus, represents the carina. Frontal area present 

 only as a minute triangular impression. Frontal carinte lyrate ; frontal groove 

 distinct. Antennal scapes slender and not flattened at the base, enlarged 

 towards their tips, which surpass by about one-sixth their length the posterior 

 corners of the head. Thorax rather long, narrower than the head, broadest 

 in front and gradually narrowed behind, but with the pleurje scarcely com- 

 pressed ; in profile rather low, arched, with pronotum somewhat flattened, the 

 mesonotum convex and the epinotum depressed and sloping, without distinct 

 basal and declivous surfaces. Petiole high and cuneate in profile, with blunt 

 border ; seen from behind, the scale is narrow at the base, gradually expanding 

 above, with broadly rounded, entire border. Gaster of the usual shape. Legs 

 rather long and slender. 



Mandibles and head opaque, the former very finely and indistinctly striated,^ 

 sparsely punctate ; teeth smooth and shining. Clypeus and cheeks irregularly 

 rugose and coarsely punctate, remainder of head densely and uniformly punc- 

 tate. Thorax somewhat shining, densely, but somewhat more superficially 

 punctate than the head ; gaster and legs still more shining, transversely sha- 

 greened ; the upper surface of the gaster also with scattered, piligerous punc- 

 tures. 



Hairs delicate, white, erect ; abundant on the thorax, petiole and gaster. 

 Head with a few long hairs on the vertex, sides with short, erect hairs ; those 

 on the truncated surface still shorter and appressed. Scapes and legs with 

 shoi't, stiff, oblique hairs, less abundant on the femora, which have a row of 

 longer, erect hairs on their flexor surfaces. Tibije without bristles on their 

 flexor surfaces. Pubescence lacking. 



Black ; mandibles, cheeks, posterior end of clypeus. anterior portion of front, 

 antennpe and tarsi, except the first joint, deep red. Posterior edges of gastric 

 segments brownish. 



Worker minor. Length, 4-5 mm. 



Differing from the worker major only in the head, which is smaller, not 

 broader than the prothorax. somewhat longer than broad, narrower in front 

 than behind, with straight sides and posterior border. It is not obliquely 

 truncated in front, but has a rather convex, sharply carinate clypeus, with 

 broadly rounded, entire anterior border. Eyes more convex, antennal scapes 

 reaching about half their length beyond the posterior corners of the head. 

 The whole head is uniformly and densely punctate and a little more shining 

 than in the worker major. Cheeks and clypeus with a few scattered foveolae. 

 Hairs on the dorsal surface of the head more abundant, those on the cheeks 

 more delicate than in the worker major. ^landibles, antennae and tarsi, except 

 the first joint, deep red ; remainder of the body black. 



Described from a single worker major and a number of minor workers 

 taken by myself on the trunk of a small desert Acacia at Fort Davis^ 

 Texas. There are also in my collection three minor workers taken by 

 Mr. C. H. T. Townsend at Cerro Chilicote, Chihuahua, Mexico, and 



