410 Bulletin American Museum of Natural History. [Vol. XXXIV, 
The pubescence on the head, gaster, and appendages though sparse, is long and 
conspicuous; the erect hairs are long, pointed and very sparse, but conspicuous on 
the occiput, thorax, pedicel and gaster. Both hairs and pubescence are pale yellow. 
The body is dark chestnut brown, the mandibles, except their borders, the middle of 
the clypeus and the cheeks and front are deep red. Antennz dark brown, legs 
paler brown. 
Worker. Length: 2.3-2.5 mm. 
Deep castaneous, head and gaster darker, mandibles, clypeus and legs reddish 
brown; punctuation of the head, thorax and pedicel coarser and deeper than in the 
typical crassicornis, only a median streak on the head and a small median spot on 
the thorax shining. Erect hairs more abundant than in the soldier, of uneven length 
and pointed; scapes with a few suberect hairs, legs with numerous more oblique hairs. 
Deecribed from seven soldiers and een workers eee in Miller Canon, 
Huachuca Mts., Arizona (alt. 5000 ft.). 
33. Stenamma brevicorne heathi subsp. nov. 
Worker. Differing from all the known North American forms of brevicorne in 
sculpture and in its much paler color. The insect is light ferruginous red throughout, 
the legs and gaster very slightly paler than the head and thorax. Some specimens 
have a vague brownish spot on the vertex. The occiput and upper surface of the 
thorax are slightly shining. The ruge of the pro- and mesonotum are coarse and 
reticulate and without longitudinal trend as in the other forms. Ruge of the post- 
petiole similarly coarse and reticulate. Spines of the epinotum very acute, fully as 
long as broad at their bases. Peduncle of petiole with a small tooth anteriorly on the 
ventral side. Eyes small, with not more than four ommatidia in their greatest 
diameter. Antennal scapes a little longer than in brevicorne and its varieties and 
reaching very nearly to the posterior corners of the head. 
Described from 25 workers taken from a single colony in King’s River 
Cafion, California, by Prof. Harold Heath. This form may deserve to rank 
as a distinct species when the winged phases are discovered. 
34. Messor chamberlini sp. nov. 
Worker. Length: 4-4.3 mm. 
Closely related to M. andrei Mayr, but much smaller, of a different color and 
with different petiole and epinotal spines. The pro- and mesonotum together are 
more convex and rounded above; the epinotal spines are not longer than the epinotal 
declivity, slightly curved, more rapidly tapering and more slender at their tips and 
directed somewhat more upward and less backward than in andrei.. In profile the 
petiole has a lower and more rounded node and its ventral surface is straight or 
slightly concave in outline (in andrei with a distinct median protuberance). The 
sculpture is like that of andrei, but not so coarse and the general surface is a little 
