electus Fouts—Nantucket pine tip moth: and G. longinervis Fouts—a western pine 
tip moth. 
Family Dryinidae 
Dryinid Wasps 
This is a small family of rarely collected insects. As far as known, all species are 
parasitic on the nymphs of Homoptera, especially the membracids, cicadellids, 
flatids, and cercopids. The females of some genera 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 intermediate between ectoparasites and 
endoparasites in the abdomens 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. The larva absorbs food from 
the host via the cyst. Aphelopus theliae Gahan, a parasite of the membracid, Thelia 
bimaculata (F.), which feeds on young black locust, lays a single egg in a nymph of 
its host. During oviposition the females secrete a substance that stops host meta- 
morphosis. Polyembryonic 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 (46/). 
Superfamily Scolioidea—Family Tiphiidae 
Tiphiid Wasps 
The family Tiphiidae contains a number of important species parasitic on 
scarabaeid larvae in soil. As far as known, all species are external parasites, usually 
feeding on the final instar of the host. The adults of most species are moderate in 
size, hairy, and black. The remainder are mostly black and yellow. A number of 
species have been imported against several introduced pests. 
Tiphia inornata Say 1s one of the most common and important parasites of white 
grubs in the United States. Infestations are heaviest during the years when full- 
grown white grubs are present. At other times, populations are usually very low 
(1348). 
Tiphia vernalis Rohwer was introduced against the Japanese beetle from Japan 
and Korea during the period 1924 to 1933. It became established and now plays an 
important role in control of the beetle in certain parts of the East, especially in 
Pennsylvania (2/7). T. popilliavora Rohwer, also introduced against the Japanese 
beetle during the 1920’s and 1930’s, is now well established from New Hampshire 
to Virginia and Ohio. T. asericae Allen & Jaynes was introduced against the Asiatic 
garden beetle and Serica peregrina Chapin during the 1920’s, and is established in 
Pennsylvania, New York, and New Jersey (697). 
Family Mutillidae 
Velvet Ants 
Members of the family Mutillidae are commonly known as velvet ants. The 
females are wingless, have heavy coatings of fine hairs, and are usually observed 
running back and forth over the ground. In certain regions they are also known as 
‘“cow-killers.”” Adults are usually brightly colored with red, orange, or yellow 
markings, and some of the females are 25 mm or more in length. The majority of 
species are parasitic on ground-nesting bees and wasps (544). A common species in 
the South, where members of the family are most prevalent, is Dasymutilla 
occidentalis occidentalis (L.). Velvet ants are capable of inflicting painful stings. 
Family Scoliidae 
Scoliids 
The family Scoliidae is represented by about 12 species in the Eastern United 
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