416 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
towards their tips which are truncate. The hairs of the thorax have 
the same form; and there are a few of them also on the border of the 
petiole (Emery). 
Emery described this subspecies from a single worker taken in 
New Mexico. For some time I attributed several specimens in my 
collection from the same state to this subspecies, but closer examina- 
tion shows them to belong to what I described as F. munda. ’ I must 
admit, therefore, that I have never seen the true obtusopilosa. My 
reasons for believing that F. munda is a distinct species are given below. 
14. EF. munpa Wheeler. 
F. pergandei var. Emery, Zool. jahrb. Syst., 1893, 7, p. 647, 8. 
F. munda Wheeler, Bull. Amer. mus. nat. hist., 1905, 21, p. 267, 8 9; Ants, 
1910, p. 458. 
WorkKER. Length 5-7 mm. 
Mandibles 8-toothed. Head, excluding mandibles, usually some- 
what longer than broad, with straight or slightly convex posterior 
border and long cheeks, converging anteriorly and slightly convex 
or flattened. Clypeus sharply carinate, with a rather deep and broad 
notch in its anterior border. Antennae slender, scapes not enlarged 
towards their tips. Thorax rather low and narrow, pro- and mesono- 
tum not very convex, mesoépinotal constriction shallow, epinotum 
long and low, its basal surface horizontal in profile and somewhat 
longer than the very sloping declivity into which it passes through a 
rounded angle. Petiole low and thick, convex in front, flattened 
behind, with a very obtuse, entire superior border. Seen from behind 
the border is transverse, broadly rounded, but passing rather abruptly 
into the straight sides, which converge below. Gaster small; legs 
slender. 
Head and thorax subopaque, very finely shagreened. Mandibles, 
anterior portion of head, and especially the borders of the frontal 
area and sides of the clypeus, more shining. Mandibles sharply 
striatopunctate. 
Pubescence grayish, sparse, except on the gaster where it is long and 
dense and conceals the shining surface, except at the intersegmental 
incisures. Hairs on the body rather abundant, glistening white, 
obtuse, suberect, and rather long on the upper surface of the head, 
thorax, and gaster; on the gaster very regularly distributed. Petio- 
lar border with a row of similar hairs. Legs invested with small, 
sparse, appressed hairs; femora and tibiae with a row of erect or 
oblique hairs on their flexor surfaces. 
