124 
Psyche 
[September 
we have examined (head width 1.08-1.32 mm) the eyes 
extend prominently beyond the margins of the head seen 
in full face. In the majority of subintegra cabinet series, 
few or none of the workers range below 1.32 mm in head 
width. In those that do, the shape of the head and place- 
ment of the eyes are highly variable. Some approach the 
curiosa condition; e. g. Broadmoor, Colo. (W. M. Wheeler) ; 
Alamogordo, N. Mex. (G. v. Krockow) ; Bronxville, N. Y. 
(Wheeler). In others, the eyes do not approach the lateral 
margins; e. g. Pullman, Wash. (W. M. Mann); Brecken- 
ridge, Colo. (P. J. Schmitt) ; Tesuque Canyon, Hyde Park, 
N. Mex. (A. C. Cole) ; Manzanares, N. Mex. (M. Cooper). 
At least one series is intermediate; Manitou, Colo. 
(Wheeler) ; associated queens here are typical subintegra 
and do not approach the curiosa color character. In general, 
variation is primarily internidal, with allometric trends 
within single nest series remaining constant. The “curiosa" 
head shape may be more common in western series of 
subintegra — at least the tendency for the production of 
smaller workers of the curiosa size class seems to be 
stronger. 
(2) Worker series from Culbertson, Mont. (E. 0. Wil- 
son) and Twin Falls, Ida. (Cole), unaccompanied by queens 
and therefore not definitely determinable, are so similar 
in pilosity and minor-worker head shape to the curiosa 
types that they have been tentatively associated with this 
species. If correctly determined, then they may provide 
the additional diagnostic character: larger workers (head 
width 1.45-1.65 mm) are present and differ from sub- 
integra workers of equivalent size by having heads pro- 
portionately more massive and with a slightly more 
quadrate frontal outline (figs. 1,2). 
(3) The body pilosity of the curiosa types and Culbert- 
son and Twin Falls series is very long and abundant, with 
numerous hairs on the mesonotum, but still within the 
extreme range of variation of verified subintegra. 
(4) The first gastric tergite, exclusive of the extreme 
posterior strip, is yellowish brown in color and contrasts 
with the remainder of the gaster in the larger curiosa 
