328 ENTOMOLOGY 
BUMBLE BEES 
Familiar as the bumble bees are, their habits are but imper- 
fectly known. The queen hibernates and in spring starts a 
colony, utilizing frequently for this purpose the deserted nest 
of a field mouse or sometimes the burrow of a mole or gopher. 
The queen lays her eggs in a small mass of pollen mixed with 
nectar (Putnam). The larvz eat out cavities in the mass of 
food and when full grown spin silken cocoons, from which the 
Imago cuts its way out; the empty cocoon being subsequently 
used as a receptacle for honey. At first only workers are 
produced and they at once relieve the queen of the duties’ of 
collecting nectar and pollen, caring for the young, etc. The 
workers are of different sizes, the smaller ones being nurses 
or builders and the larger ones foragers—the kind commonly 
seen out of doors. In the latter part of summer both males 
and females are produced, but when severe frost arrives, the 
old queen, the workers and the males succumb, leaving only 
the young queens to survive the winter. 
SocIAL WASPS 
The Social Wasps constitute the family Vespidz, of which 
we have three genera, namely, Vespa, Polistes and Polybia, 
the last genus being represented by a single Californian species. 
Vespa.—Some species of Vespa, as l’. maculata, make a 
nest which consists of several tiers of cells protected by an 
envelope (Fig. 281), attaching the nest frequently to a tree; 
other species, as germanica and vulgaris, make a nest under- 
ground. ‘The paper of which the nests are composed is manu- 
factured from weather-worn shreds of wood, which are torn 
off by the mandibles and then masticated with a secreted fluid 
which cements the paper and makes it waterproof. 
A solitary queen founds the colony in spring; she starts the 
nest, lays eggs, feeds the young and brings forth the first 
workers; these then relieve her—continue the building opera- 
tions, collect food, nurse the young, in short, assume the bur- 
den of the labor. In the latter part of summer, fertile males 
