254 PROCEEDINGS OF THE ACADEMY OF [Feb., 



as long as broad, much stouter than the succeeding joints, except 

 those of the 4-jointed chib; joints 3-7 longer than broad; three basal 

 joints of club subequal, each not more than half as long as the terminal 

 joint. Cheeks short. Thorax with very deep Mayrian and other 

 sutures. Epinotum without indications of spines. Petiole and post- 

 petiole longer and with lower nodes than in the worker. Gaster of the 

 usual shape. 



Mandibles and clypeus somewhat shining, the latter with a few 

 prominent and irregular longitudinal rugse. Head decidedly opaque, 

 uniformly and densely punctate. Thorax shining, mesonotum, scu- 

 tellum and pleurae with faint, parallel, longitudinal striae. Pronotum 

 and epinotum more reticulate-rugose. Petiole and postpetiole smooth 

 and shining on the summits of the nodes, elsewhere subopaque, finely 

 reticulate-rugose. Gaster smooth and shining. 



Hairs covering the body sparse, whitish, non-clavate, longest and 

 most conspicuous on the gaster, very small and appressed on the legs 

 and antennae. 



Black, thorax and pedicel more piceous, especially on their lateral 

 and ventral surfaces. The following parts are yellowish, or yellow 

 suffused with piceous: mandibles, except their teeth, which are black, 

 antennae, legs and genitalia. Wings whitish-hyaline, veins and stigma 

 colorless. 



Type locality : King's Cafion, Ormsby county, Nev. 



Described from eight workers, one female and eight males, found by 

 ]\Ir. C. F. Baker during August, 19n2, nesting in the ground under a 

 stone. 



This species appears to be similar to L. tricarinatus Emery, but differs 

 in the shape of the clypeus, which is impressed and sinuately excised 

 and not produced, and in the shape of the epinotal spines, petiole, etc. 



17. Leptothorax terrigena sp. nov. 



Worker (PL XII, fig. 21).— Length 1.5-1.75 mm. 



Head rather narrow, with parallel sides. Mandibles 5-toothed. 

 Clypeus moderately convex, without median impression and with 

 broadly rounded, non-sinuate anterior border. AntennjB 12-jointed, 

 scape extending to f the distance between the eye and the posterior 

 corner of the head; first funicular joint as long as the three succeeding 

 joints together; joints 2-8 of funiculus decidedly broader than long, 

 subequal ; three terminal joints forming a distinct club, of which the two 

 basal joints are subequal in length but not in thickness, and together 

 shorter than the terminal joint. Thorax slender, somewhat broader 

 in front than behind, with rounded humeral angles and moderatelv 



