166 S. B. Buckley on North American Formicidx. 



Dwells in the ground near the surface, in the vicinity of Fort Ma- 

 son, in Western Texas. 



24. Formica saxicola. n. sp. 



Female. Length 0.17 inch. — Head and ahdomen subpiceous or 

 brownish-black ; thorax and legs reddish-brown ; head small, triangu- 

 lar, about half the width of the thorax, rounded and smooth above ; 

 ocelli placed near the vertex ; eyes large, placed about midway of the 

 upper portion of the sides of the head ; antenna3 filiform and slightly 

 enlarged towards the apical joint; mandibles small, flattened and nar- 

 rower in the middle portion, curved inwards, and with four small teeth 

 on the inner apical margin ; thorax large, raised above the head, with 

 the principal divisions slightly marked; pedicle short; scale small, erect 

 and compressed; abdomen large, oblong-ovate; legs slender and rather 

 short; whole ant smooth and shining; wings not seen. 



Worker. Length 0.11 inch. — Color yellowish-brown; head trian- 

 gular, wider than the thorax; eyes small; ocelli absent; mandibles 

 small ; thorax with the divisions strongly marked ; mesothorax some- 

 what depressed; abdomen ovate; legs long and slender; legs and un- 

 der surface of the whole body honey-yellow ; otherwise like the fe- 

 male. 



Hah. — Beneath rocks in Buchanan County in Northern Texas. 



25. Formica discolor, n. sp. 



Female. Length 0.30 inch. — Anterior wings extending about 0.10 

 inch beyond the abdomen, with one marginal and two submarginal 

 cells, discoidal cells obsolete; head, thorax and legs reddish-brown, ex- 

 cepting the upper portion of the mesothorax which is black; abdomen 

 black; eyes small, circular, black, lateral, placed near the upper sur- 

 face, a little behind the middle part of the head ; antennae inserted in 

 front, filiform; mandibles widened and curved inwards anteriorly, with 

 their inner apical margins 5-toothed ; head broader than the thorax, 

 subquadrate, rounded above, a deep cavity beneath the occiput; pro- 

 thorax raised above the head, rounded above; meso- and metathorax 

 small, with the divisions well marked; pedicle short; scale large, ver- 

 tical and compressed, with edges somewhat sharp ; abdomen oblong- 

 ovate, subobtuse, with a few scattering short hairs in the margins of 

 the posterior segments ; legs somewhat short and slender; tibiae and 

 tarsi of a darker shade than the coxa) and trochanters. 



Worker. Length 0.26 inch. — Head thorax and legs reddish-brown ; 

 abdomen ovate, black ; mandibles brownish-black; thorax compressed 

 aud narrowed posteriorly; prothorax about half the width of the head; 



