poe 
Vol. VI 
34 WHEELER — TWO NEW ANTS 
nearly straight. Clypeus distinct, subtriangular. Thorax narrower than 
the head, longer than broad, broadest through the pronotum, flattened 
above, without pronotal crest, with distinct promesonotal and very indis- 
tinct mesoépinotal sutures. Each side of the pronotum bears a pair of 
subequal acute spines in front and a rectangular tooth behind. Epinotum 
with a pair of spines as long as those at the anterior corners of the pronotum. 
Petiole and postpetiole similar to those of the soldier but of more nearly 
equal breadth, and the postpetiole is proportionally longer. Gaster regu- 
larly elliptical, like that of the soldier, without anterolateral ridges. 
Sculpture like that of the soldier, but the foveole on the head and thorax 
smaller, the thoracic dorsum, mesopleure and sides of epinotum also 
coarsely longitudinally rugose, and the gaster finely longitudinally rugose 
over its whole surface. 
Erect, obtuse, silvery white hairs more abundant than in the soldier, 
and present also on the upper surface of the head and gaster. The silvery 
appressed hairs are longer and more conspicuous, and occur in the foveol 
over the whole dorsal surface as well as on the petiole and postpetiole. 
Color like that of the soldier. The expanded frontal carine are deep 
reddish, as are also the tips of the antenne, the mandibles, tips of tibixe 
and the terminal tarsal joints. 
Described from two soldiers and two workers received from Mr. S. A. 
Rohwer. These and a series of cotypes in the National Museum were taken 
by Mr. Chrisman in Buckman Canyon, Santa Catalina Mountains, Ari- 
zona. Mr. Rohwer writes me that the ants were found ‘‘in galleries exca- 
vated at the base of dead limbs and against the green wood of palo verde 
(Cercidium torreyanum). Mr. Chrisman states that these ants are quite 
common in that vicinity, always occurring in galleries in this tree.’ 
C. rohwert can be readily distinguished from C. wheelert, which I 
found many years ago nesting in epiphytes (Tvllandsia) near 
Cuernavaca, Mexico, by its somewhat larger size (the soldier of 
wheelert measures only 5—5.5 mm., the worker only 3.2-3.6 mm.), 
and by several peculiarities of structure, sculpture, pilosity and 
color. Most of the structural differences will be apparent from a 
comparison of the figures (fig. 2, a—d). In the soldier of wheeleri 
(fig. 2, c) the border of the cephalic saucer is much lower laterally 
and posteriorly than in rohweri, but the anterior translucent portion 
is somewhat more extensive, and the top of the head forming the 
floor of this structure is flattened behind and transversely convex 
in front. The pronotal crest is more distinctly interrupted in the 
middle, the surface of the body and especially of the gaster is dis- 
