172 
A single pair occurred on Haleakala, Maui, at an elevation 
of about 5000 feet. 
45.— Crabro rubrocaudatus. 
C. rubrocaudatus, sp. nov. ^ vix nitidus ; puhescens; 
obscure punctatus ; niger, alis late cceruleis ; abdomine in 
medio lato, segmentis sexto et septimo dense aureo-pilosis. 
Long. 10 mm. 
The head and thorax are excessively finely punctured, and 
are obscurely and confusedly sprinkled with a larger 
system of punctures. The punctuation is rougher and 
more obscure on the metathorax than on the anterior 
parts, and there are some conspicuous oblique 
wrinkles about its sides. The first five segments of 
the hind body are brightly shining, and are dis» 
distinctly finely and rather closely punctured, without 
much pubescence. The apical two segments are verj’^ 
conspicuously and densely clothed with long golden 
red hair. The pubescence of the head and thorax is 
rather dense but not conspicuous, being of a dark 
colour. The wings are of a beautiful clear blue (it is 
remarkable in how many of the Hymenoptera taken 
near the crater of the active volcano this colour 
appears). The eyes are separated in the last two 
species named above and are excessively finely facetted. 
The face is little concave. The denticulation of the 
6th joint of the antennas is only moderate. The 
ventral segments resemble those of G. stygius and 
adspectans. 
In the same locality as th $ rubrocaudatus I procured 
two examples, which are probably its female. As, 
however; they differ rather exceptionally, I hesitate 
to assign them to this species with certainty, for the 
wings are entirely devoid of the blue tint. In other 
respects they might well be 9 rubrocaudatus. The 
penultimate and apical segments in the hind body of 
