FAMILY SPHECIDAE 
This family is represented by 86 genera and scores of species in 
the United States and Canada. The majority are solitary nest- 
building wasps which provision their nests with other insects or 
spiders. Many species nest in the ground; some construct nests of 
mud and attach them to the ceilings or walls of buildings or to 
the lower surfaces of other objects; others construct their nests 
in the stems of plants. Adults are distinguished by the presence 
of an anal lobe and several closed cells in the hindwing, the 
presence of seven exposed tergites on the abdomen of the male, 
the failure of the hypopygium to enclose the sting in the female, 
and the lack of dilation of the hind tarsus. In a few species, such 
as the familiar dirt-daubers, the petiole of the abdomen is greatly 
lengthened. 
The cicada killer, Sphecius speciosus (Drury), which provisions 
its nest with adult cicadas, is the most conspicuous member of the 
family. The adult female is a large, black or yellow wasp up to 37 
mm. long. There are prominent black and yellow bands or spots 
on the abdomen and the ovipositor or stinger is long and curved. 
Adults are usually present from midsummer to early fall and they 
burrow into the ground for nesting purposes. The female para- 
lyzes a cicada by stinging it and then carts it to her nest, stores it 
in a cell, and deposits an egg between its legs. When the larva 
hatches it feeds on the cicada. There is one generation per year. 
Cerceris fumipennis Say provisions its nests with a wide 
variety of wood-boring buprestids. Species of the genus Psen 
Latrielle prey on various membracids, cereopids, and leafhoppers. 
Crossocerus ambiguus (Dahl) preys on various species of tree- 
infesting cicadellids (184) ; Stictia carolina (Fab.) is frequently 
seen hovering over livestock in search of horseflies. 
FAMILY DRYINIDAE 
This is a small family of rare insects. As far as known, all 
species are parasitic on the nymphs of Homoptera, especially the 
membracids, cicadellids, flatids, and cercopids. The females of 
certain species are wingless and antlike. Also, in most species 
they differ so much in appearance from the males that the two 
sexes can be associated only by rearing them. 
During the larval stages, these insects are internal parasites of 
the abdomen of their hosts. Usually one or more external gall-like 
cysts develop on the integument of the host. These cysts which 
may be as large as the abdomen of the host, contain the parasite 
larvae. Aphelopus theliae Gahan, a parasite of the membracid, 
Thelia bimaculata, which feeds on young black locust, lays a 
single egg in a nymph of its host. Polyembronic development takes 
place and from 50 to 75 parasites are produced in the nymph. 
When they reach maturity, they bore through the body wall and 
drop to the ground to pupate (278). 
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