342 S. B. Buckley on North American Formicidx. 



angles rounded, sides nearly parallel; eyes lateral, black, small, circu- 

 lar, placed about midway of the head ; antennae short, clavate, head 

 slightly channeled below, a small depression beneath the occiput ; 

 madibles small, subtriangular. curved inwards, sharp-pointed, inner 

 margins toothed; prothorax small, narrower than the head, rounded 

 above; mesothorax depressed and sub-strangulated at its junction with 

 the metathorax ; metathorax large, sloping gradually to the pedicle, 

 smooth and oval above; scales large, nearly equal, rounded; abdomen 

 ovate, subacute ; legs long, slender; whole ant smooth. 

 Beneath rocks, in Buchanan County, Texas. 



51. Myrmica (Monomarium) atra, n. sp. 



Worker. Length 0.15 inch. — Jet black, smooth and shining: tibiae 

 and tarsi subhyaline; head ovate, round above, at the sides and pos- 

 terior angles; eyes small, circular, prominent, lateral, in front of the 

 middle; antennae clavate, at base of the clypeus ; mandibles small 

 curved inwards and downwards, acute, head not channeled below ; 

 prothorax a little wider than the head, rounded above, and slightly at 

 thesldes; the divisions of the thorax slightly marked, being widest at 

 the mesothorax, and gradually narrowed back ; metathorax slightly 

 depressed, subtruncate ; pedicle long; scales subnodose, anterior one 

 small and sub-wedge-shaped; abdomen large, ovate, oblong, subobtuse; 

 legs short, slender; the whole ant smooth and without hairs. 



On trees, near Georgetown, D. C. Bare. 



52. Myrmica (Tetmamorium) exigua, n. sp. 



Female. Length 0.16 inch. — Black or piceous, legs dark -brown or 

 hyaline ; head very small, broad-ovate, somewhat rounded above and 

 behind; antennae clavate, long, filiform, at base of the clypeus; eyes 

 very large, prominent, subelliptical, lateral, and placed in front of the 

 middle; mandibles small, curved inwards, acute ; ocelli at the top of 

 the occiput ; prothorax large, wider than the head, rounded above and 

 below, and slightly at the sides, larger than both meso- and meta- 

 thorax ; mesothorax not depressed, somewhat rounded above; meta- 

 thorax depressed, subtruncate; pedicle long; scales small, nodose, 

 posterior one the largest; abdomen ovate, narrowed before and back, 

 widest in the middle; legs short, slender; smooth throughout. 



Worker: Length 0.06 inch. — Tale-yellow, upper surface of the 

 head yellowish-brown ; head oblong-ovate, rounded above and slightly 

 so at the sides, widest in the middle, divisions of the thorax well 

 marked ; mesothorax rounded above, and also the metathorax, which 

 descends gradually to the pedicle; scales nodose, anterior one largest; 

 abdomen small ; otherwise like the female. 



