WASPS AND BEES. 
131 
in gravelly walks, and have the instinct to sting grass- 
hoppers in one of the thoracic nerve-centres, thus ])aralyzing 
the victim, in which the wasp 
lays her eggs; the young hatch- 
ing, feed upon the living but 
paralyzed grasshoppers, the 
store of living food not being 
exhausted until the larval wasp 
is ready to stop eating and ^ 
finish its transformations. ^^-^ 
The genuine paper- making 
wasps are numerous in species; t^.l^^ml 
here the workers are winged, 
and differ from the females or 
queens in being rathei- smaller. 
Odynerus builds cells of mud. 
The genuine paper-making 
wasps, such as Vespa, build 
several tiers of cells, arranged 
mouth downward, and envel- 
oped by a wall of several thick- 
nesses of paper. In the Vespce, 
the females found the colony, 
and raise a brood of workers, 
which early in the summer 
assist the queen in completing 
the nest. 
The bees also present a grad- 
ual series from those which 
are solitary, living in holes in 
the earth, like the ants (Fig. 
173), and forming silk-lined 
earthen cocoons, to those Fig 173.— Nest of Andrena. g, level 
, . , . , . . , . T of ground ; a, first-made cell, con- 
which are social, with Wmged taming a pupa; 6, larvae; e, pol- 
1 TT-^ij-i» • £ len mass with an egg laid on it; /, 
workers, slightly differing from poiien mass freshil deposited by 
the queens. The queen hum- 
ble-bee hibernates, and in the spring founds her colony by 
