258 
Psyche 
[September-December 
Parancistrocerus vagus (Saussure) 
Some years ago I reported briefly on a mud nest of this species 
found on a willow branch in Kansas (Evans, 1956). I take this 
opportunity to include a photograph of a very similar nest found 
on 4 June 1974 at Mescalero Sands, east of Roswell, New Mexico 
(Fig. 3). The nest was on the branch of a mesquite bush ( Prosopis 
juliflora) 0.6 m above the ground. The nest measured 3.4 X 1.9 cm 
and contained 6 cells, two of which were empty. Cells measured 6' 
X 13 mm. Two contained cocoons, one a large eumenid larva, and 
one nothing but dried, shriveled larvae of Microlepidoptera which 
were in too poor condition to be identified. The female wasp 
rested on the outside of the nest in a small hollow which would 
probably have formed the floor of a new cell. 
The two cocoons both yielded cuckoo wasps, Chrysis dugesi 
Buysson, 2-3 weeks later. 
Discussion 
These three examples reinforce the impression that certain 
aspects of nesting behavior are relatively fixed in Eumenidae 
(oviposition and type of prey) while others are diverse and not 
closely correlated with generic divisions based on structure (loca- 
tion and type of nest). Eumenidae are largely solitary nesters, and 
it may be some years before enough information has accumulated 
to clarify the patterns of evolution within the group. The occur- 
rence of delayed provisioning in Euodynerus auranus is of interest. 
This occurs in certain other Eumenidae and is regarded as one of 
several preadaptations for social life in wasps (Evans, 1958). 
Oviposition in the empty cell and use of materials from sources 
other than the immediate substrate provide other preadaptations; 
some Eumenidae use plant materials in nest construction (Bohart 
& Stange, 1965). Species of Montezumia are evidently communal 
nesters and progressive provisioners (Evans, 1973). Thus there is 
every reason to regard the Eumenidae as providing the ancestral 
stock of the social Vespidae. 
Acknowledgments 
I am indebted to R. M. Bohart for identifying the Eumenidae 
and Chrysididae and to D. M. Weisman for identifying the Lepi- 
