FAMILY PERILAMPIDAE 
This is a small family with only two genera and 31 species in 
the United States and Canada. Its members are secondary para- 
sites of various Diptera, Hymenoptera, Orthoptera, and Neurop- 
tera. The pupae of tachinid, braconid, and ichneumon parasites 
are especially attractive. 
Perilampus hyalinus Say, a common species throughout the 
United States, is a secondary parasite of a large number of insects 
in which it develops at the expense of many species of primary 
tachinid and ichneumonid parasites. The adult is bright, metallic, 
bluish-green and is from 2 to 4 mm. long. The thorax is large and 
the abdomen triangular. Peck (588) lists more than 20 species of 
Orthoptera, 16 species of Lepidoptera, 12 species of sawflies, and 
many species of ichneumonid, sarcophagid, and tachinid parasites 
as hosts. Smith (657) discussed its biology as a secondary parasite 
of the fall webworm. 
FAMILY TORYMIDAE 
Most members of this fairly large family are parasites of gall- 
forming insects. A number of others are parasitic on various 
lepidopterous larvae; quite a few feed in the seeds of various 
plants; and some act as hyperparasites. 
The genus Torymus Dalman contains a large number of species 
that parasitize the immature stages of gall-forming cynipids and 
cecidomyids. T. rugglesi Milliron has been collected from the 
seeds of American holly in Delaware. 
Members of the genus Megastigmus Dalman are all phytopha- 
gous, developing in the seeds of plants. Eastern species include 
M. amelanchieris Cush.—on shadbush; M. laricis Marcovitch—on 
larch; and M. specularis Walley—on balsam fir. The latter has 
destroyed up to 40 percent of balsam fir seed during certain years 
in eastern Canada. 
The genus Monodontomerus contains several important para- 
sites of various species of Lepidoptera and sawflies. M. dentipes 
(Dalman), a European species which probably entered this coun- 
try with its European host, the introduced pine sawfly, is now 
widely distributed in southeastern Canada and in northern States 
from Maine to the Lake States. It is not only an effective parasite 
of the introduced pine sawfly, but also an important parasite of 
several other sawflies attacking conifers. It spends the winter as 
a prepupa inside the host cocoon. Adults appear over a fairly long 
period in the spring and lay their eggs through the host cocoon, 
depositing several upon the prepupa. There are probably two 
generations per year. 
Monodontomerus aerus Walker was introduced into New Eng- 
land from 1906 to 1910 against the gypsy and brown-tail moths. 
It was released originally as a primary parasite but is much more 
common as a hyperparasite, attacking both hymenopterous co- 
coons and tachinid puparia. It is also parasitic on the white- 
marked tussock moth and the eastern tent caterpillar. 
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