164 S. B. Buckley on North American Formicidse. 



pro-thorax round above, in front and at the sides, widest in the middle; 

 rnesothorax narrowed behind, a small strangulation betweeu it and the 

 metathorax; metathorax raised, widened behind, truncate; abdomen 

 small ovate; legs long, slender; otherwise like the female. 



Male. Length 0.34 inch. — Trochanters, tibiae and tarsi pale yellow; 

 head very small aud one-third narrower than prothorax ; eyes very 

 prominent, large, lateral, and gray; abdomen oblong-ovate; the rest 

 like the female. 



Dwells in trees. Texas. 



21. Formica festinata. n. sp. 



Female. Length 0.50 inch. — Honey-yellow, with dark brown on 

 the abdomen, thorax and head ; wings projecting but little beyond the 

 abdomen, with one marginal and two submarginal cells; head oblong- 

 subtriangular, rounded and smooth above, emarginate behind, posterior 

 angles rounded; eyes black, large, prominent, placed on the sides of 

 the head near the anterior portion of the occiput; ocelli situated back 

 of the vertex on the upper part of the occiput; antenna long, filiform; 

 mandibles brownish-black, short, large, curved inwards, having each 

 seven blunt teeth on the inner margins; thorax about equal in width 

 to the head, its sides compressed and narrowed posteriorly; posterior 

 margin of the prothorax and entire upper margin of the rnesothorax, 

 blackish-brown, the margins being slightly raised, metathorax lower, 

 oval, smooth and rounded; pedicle short, scale large, erect and some- 

 what compressed; abdomen oblong-ovate, with a few scattering hairs 

 on the margins of the segments which are brown or brownish-black; 

 legs long, slender. The entire insect is smooth and shining. 



Worker. Length 0.jJ8 inch. — Honey-yellow, or colored like the fe- 

 male; ocelli none; head wider than the thorax; thorax smooth, with 

 the divisions well marked; abdomen ovate, pointed; the remainder 

 like the female. 



The workers of this species vary in size and somewhat in color, the 

 largest being often tinged with brownish-black like the females. Those 

 tinged are probably the oldest, and this may be the cause of the ditfer- 

 ance. The length given is that of on 3 of the smallest. Both sizes 

 work in common. They are very active, travelling beneath rocks or 

 sticks where they have cells and galleries in the earth to the depth of 

 twelve or eighteen inches. They are not war-like, and rarely bite when 

 caught, nor are they often seen in the open air, hence they prubably 

 seek food by night. 



Common in Central Texas. Winged females caught in September. 



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