THe HyMENOopPTERA oF MINNESOTA PAUL 
bushes. These nests are said to have served as models for early In- 
dian pottery. 
The group is of great economic importance, valuable to fruit 
growers and farmers, for its members prey upon caterpillars and larvae 
of beetles, many thousands of which it destroys each year. Some- 
times as many as from six to a dozen are found in one cell. Cater- 
pillars are first paralyzed by being stung, and, to insure safety for the 
single egg, the latter is suspended by a thread from the roof of the 
cell. The different species destroy numbers of tineids, geometrids, 
tortricids, and noctuid moths during the season. 
There is no worker caste in 
this family, all duties being per- 
formed by the perfect female. 
A few of the species resemble 
“yellow jackets” so closely that 
they fill one with alarm. 
In some genera, Eumenes for 
example, the pedicel at the base 
of the abdomen is very elongate, 
Fig. 101. Odynerus flavipes and its nest built Ww hile 7 others, It 1s strikingly 
HE EE SOUL ftekee LON ENe short. In fact, Odynerus has a 
sessile abdomen. 
Odynerus capra Sauss. provisions its cells with the larvae of the 
destructive larch saw-fly. This genus lives in holes in walls, in posts 
or other woodwork, in burrows in earth, or in stems of plants. 
Ashmead states that in Florida he has observed O. errynis St. 
Farg. making its nest in the lock of his front door and in old holes 
in his board fence. He also reared it many times from cells con- 
structed in old oak galls. C. V. Riley found an Odynerus cell in the 
tunnel through the center of a spool. Fig. 101. 
The following species may be credited to Minnesota: Odynerus 
(Ancistrocerus) capra Sauss., O. foraminatus Sauss., O. molestus 
Sauss., (see colored plate 1.) Eumenes fraterna Say, on Aster in Aug. 
and Sept., Odynerus sp. taken at Itasca Park, Itasca Co. Aug. 22 and 
29 and Sept. 1, in Roseau Co. Aug. 19 and in Rock Co. Sept. 11. 
VESPIDAE 
Same as Eumenidae, but claws simple. Three forms, females, males, and work- 
ers; abdomen either sessile or petiolate. 
This family contains our social wasps, living in communities and 
constructing dwellings of papery-like material. This is made of woody 
