6o 
Psyche 
[March 
Chrisman’s specimens came from C. microphyllum and not from 
C. torreyanum. The list in Table i is an expanded version of the list 
of localities for rohweri which M. R. Smith presented in his 1947 
study of Cryptocerus (2). 
While this list is unbalanced by the preponderance of records from 
the Santa Catalina Mountains it permits several conclusions. The 
range of rohweri covers a number of mountainous areas in southern 
Arizona. In each of these areas rohweri prefers to nest in canyon 
bottoms or on foothills at comparatively low elevations (2800-3700'). 
Although as yet unconfirmed, it is certain that the range of rohweri 
extends into northern Sonora. Pena Blanca Springs is (or perhaps 
better “was”, for the area has been dammed and flooded) about five 
miles north of the border of Sonora and the mountains there run south 
into Mexico. It is clear that rohweri will accept at least four different 
trees as nest sites ( Cercidium microphyllum , Prosopis juliflora, 
Q'uercus emoryi and Celtis sp.). Despite the large number of records 
from palo verde there are indications that rohweri has no special 
preference for this tree. In 1954 Creighton and Gregg showed that 
Crypt, texanus prefers to live in live oaks (3). This view was based 
not only on a preponderance of records for nests in live oak limbs but 
also on the fact that texanus nests in live oaks wherever these occur 
within its range. If rohweri prefers to nest in palo verde limbs it 
might be expected to do so over its entire range. As far as we have 
been able to determine it does not do so. In January of 1963 the 
senior author made an extensive survey of palo> verde trees in the 
area between Benson and Ajo. This survey failed to produce a single 
nest of rohweri. Negative evidence of this sort is not conclusive but 
at least it may be said that the high incidence of rohweri nests in palo 
verde limbs in the Santa Catalina Mountains is not maintained in 
other parts of its range. It is possible that our present fragmentary 
view of the range of rohweri is an outcome of the fact that the tree 
which it prefers as a nest site has not yet been recognized. 
Most of the observations in the remainder of this paper are based 
on three captive colonies of rohweri. One of these was observed by 
the junior author from October 1961 until August 1963. During 
this period the colony was studied at Tucson, less than five miles from 
its original nest site in the Santa Catalina Mountains. The senior 
author was less fortunate for the two captive colonies which he 
observed were carried far out of their range. From January to mid- 
April of 1963 they were studied at Riverside, California. Thereafter 
until June 1964 they were studied at Rockport, Ontario. It would 
appear, however, that these expatriate colonies behaved in a normal 
