RECORDS AND FLOWER PREFERENCES 
OF MASARID WASPS 
(HYMENOPTERA: VESPIDAE) 
By 
Kenneth W. Cooper (Princeton University) 
and 
J. Bequaert (Harvard University) 
The observations which follow on the masarid wasps in Colorado 
are based largely upon collections made (by KWC) in the vicinity 
of the Science Lodge of the University of Colorado during the in- 
terval July 26 — August 21, 1949. Additional flower records and 
information upon eleven species of Pseudomasaris from Arizona, 
California, Oregon, South Dakota, Texas and Utah, as well as 
from Colorado, are included (by JB) from previously unpublished 
notes. All records, therefore, rest on the authority of Dr. J. Bequaert 
if they are not initialled “(KWC)”. 
Science Lodge, it should be remarked, is located at the margin 
of Arapaho Moraine, below Mount Niwot, approximately eight miles 
NNW of the town of Nederland, Colorado, at an altitude of 9,528 
ft., just three miles East of the Continental Divide. It is thus in 
the uppermost fourth of Ramaley’s “Montane Zone”, heavy stands 
of lodgepole pine characterizing the region. Road margins and 
clearings were frequently densely populated with flowers very at- 
tractive to aculeate Hymenoptera, and collecting could hardly have 
been better. The varied terrain with predominantly ponderosa 
pine-Douglas fir forests below, subalpine fir-Engelmann spruce 
stands and tundra above, all make Science Lodge located in the 
intermediate lodgepole pine forest ideally situated as a central base 
for the field naturalist. 
The records which follow may be added to those of Bradley 
(1922) and Bequaert (1929, 1940, 1943). As many of the older 
records of Pseudomasaris flower preferences are today uncertain 
because of obvious misidentification of the plant concerned, it is 
very important that all new records be validated by authority. The 
137 
