420 Bulletin American Museum of Natural History. [Vol. XXXIV, 
Described from numerous individuals taken from a single colony at 
Brookdale, California, by Prof. Harold Heath. The slave ant accompany- 
ing these specimens belongs to a small variety of Formica fusca L. near the 
var. argentea Wheeler. 
50. Polyergus rufescens leviceps subsp. nov. 
Worker. . Length: 4-5.5 mm. é 
Decidedly smaller than the subsp. breviceps Emery and of the same size as the 
subsp. bicolor Wasmann, but differing from both in the shorter and more sudden 
enlargement of the tips of the antennal scapes and in the surface of the body which is 
much smoother and more shining throughout. The head, especially, is conspicuously 
glabrous and shining. Pubescence on the thorax and gaster as in breviceps and the 
color is the same, except that the apex-of the gaster behind and including the posterior 
margin of the second segment is black. In many specimens the posterior margin 
of the first segment is also more or less infuscated. 
Described from numerous specimens belonging to two companies of 
workers which I found making slave raids on the slopes of Mt. Tamalpais, 
near San Francisco, Cala., July 19, 1914. The ants from whose nest they 
plundered the brood belonged to Formica subpolita Mayr. 
ol. Camponotus acutirostris Wheeler var. clarigaster var. nov. 
Worker Major. Wength nearly 12 mm. 
Differing from the typical acutirostris in having the gaster reddish yellow through- 
out like the thorax; the antennal scapes and first funicular joint, tibize and metatarsal 
joints black; the mandibles nearly black, the clypeus dark red and the tips of the 
femora infuscated. From the var. primipilaris Wheeler it differs in its smaller size 
and in lacking the infuscation of the gaster and pronotum. 
A single specimen taken at an altitude of about 3000 ft. on the Bright 
_ Angel Trail in the Grand Cajfion, Arizona. The large number of acutirostris 
_ specimens which I collected in the Huachuca Mts., Arizona, make it seem 
possible that this form, and its vars. primipilaris and clarigaster are merely 
stature and color varieties of C. ocreatus Emery, but till I see unmistakable 
worker specimens of this ant, I hesitate to regard the specific name acutiros- 
tris as a synonym. 
o2. Camponotus yogi sp. nov. 
Worker Major. Length: 8 mm. 
Head rectangular, fully 14 times as long as broad, with straight, parallel sides 
and broadly excised posterior border; in profile convex above, obliquely truncated 
anteriorly and flat below. Eyes rather large, elliptical, well behind the middle of 
the sides of the head. Mandibles small, thick, wedge-shaped in profile, their outer 
