56 
Psyche 
[September 
Observations on Colony at Rodeo, New Mexico 
1 his small colony of Bembix u-scripta was discovered on August 28, 
1959, in open desert at about 4000 feet elevation one mile north of 
the town of Rodeo, in extreme southwestern New Mexico. The area 
in question has only a few shrubs and small trees (chiefly mesquites 
and yuccas), but following the summer rains it is densely covered with 
composites and other flowering annuals, Russian thistle, and grasses. 
Here and there are small places devoid of vegetation. In some of 
these the ground is flat and the soil rather compacted, while in others 
the soil is loose, sandy, and somewhat blown-out or piled up in small 
dunes no more than a meter or two high. One of these small dunes 
contained about six nests of Bembix u-scripta , while two other nests 
were found in similar places not far distant. A colony of A philanthops 
haigi was located in the same dune with most of the Bembix nests, the 
nests of the two wasps intermingled. A few specimens of Bembix sayi 
and B. Similans also nested within the total area inhabited by B. u- 
scripta. 
Many things about this situation were strikingly different from the 
Port Isabel location. The season was of course different, though 
August is properly considered “spring” in this area, as the summer 
rains occur in July and August and result in a great flowering of the 
desert and in the appearance of many Hymenoptera. The soil here 
was of finer texture, more friable, and apparently drier, although oc- 
casionally moistened temporarily by showers. No tests were made to 
determine whether the soil was of comparable salinity, but surely it 
was not, as this is not an area of notable internal drainage such as oc- 
cur in some parts of the Southwest. 
The total population of Bembix • u-scripta in this area may have 
been no more than 30 to 40 individuals of both sexes. Consequently, 
in spite of the longer period of study (August 28- September 12), my 
data are more fragmentary. However, I was especially alert for re- 
semblances to and differences from the Texas colony, and the follow- 
ing account stresses these. 
Behavior of males. — The first males were observed August 21 fly- 
ing over certain bare, sandy patches, although no females were dis- 
covered until a week later. The flight of the males was extremely 
rapid and the pattern of flight very irregular; it was only after many 
failures that I succeeded in taking one for identification. There were 
scarcely enough males for a typical “sun dance”, though now and then 
two or three would fly about the same small area and make contact 
