about 37 mm. The head is light brown; the body is dark brown 
to almost black with a broken white line on either side and two 
conspicuous red spots near the posterior end. There are also nu- 
merous tubercles with long, barbed hairs and many short, brown 
hairs on the dorsum and sides. These hairs are poisonous to man 
and cause a severe rash when they come in contact with the skin. 
Adults appear in early July, and the female deposits her eggs 
in elongate oval masses from 12 to 18 mm. long on the undersides 
of leaves. Each mass contains about 300 eggs and is covered with 
brown hairs from the female’s abdomen. Young larvae feed gre- 
gariously on the surface of the leaves. Later, they tie two or more 
leaves together with silk near the tip of a branch. Then they spin 
a web over the outside of these leaves and fasten them securely 
to the twig, thereby forming a tough, grayish web from 2 to 6 
inches long where they spend the winter. Feeding is resumed in 
the spring, and the larvae become full-grown by mid-June. Pu- 
pation occurs in silken cocoons spun usually among the leaves at 
the tips of twigs (121). 
The brown-tail moth, although one of the better known forest 
and shade tree insects in eastern United States, is no longer of 
economic importance. For some undetermined reason, it has al- 
most disappeared. Introduced parasites, many of which became 
established (205), and a fungus disease probably helped toward 
its control, but it seems unlikely that they were primarily respon- 
sible for its decline. 
FAMILY LASIOCAMPIDAE 
TENT CATERPILLAR MOTHS AND ALLIES 
The family Lasiocampidae is represented in North America by 
less than 30 species, several of which are important economic 
pests of trees. The moths are medium-sized and stout-bodied; the 
body, legs, and eyes are hairy; and the antennae are somewhat 
feathery. The larvae vary in form from nearly cylindrical to very » 
much flattened; they are very hairy. 
The majority of important species belong to the genus Mala- 
cosoma Hubner, and are commonly known as tent caterpillars. 
Four and a possible fifth species occur in eastern United States 
and eastern Canada. The remaining eleven North American spe- 
cies have a western distribution. The genus was recently revised 
by Stehr and Cook (687). They include keys to the adults, ma- 
ture larvae, and egg masses of all species. They also discussed 
their distribution, their hosts, and some of their habits. 
Eggs of tent caterpillar moths are laid either in flattened 
masses on the bark of limbs or trunks of trees or in masses that 
may encircle small twigs. The number of eggs per mass ranges 
from 100 to 400, usually from 150 to 250. As the eggs are de- 
posited, they are held in place by a frothy substance called spu- 
maline (358). The majority of species also cover their eggs with 
this material. Hatching occurs in the spring, about the time the 
new leaves of the host tree appear. Young larvae feed first on 
ege shells, then on the buds and young leaves. Those of tent- 
building species also begin immediately to construct a tent on a 
branch or in a nearby crotch. They do not feed from within the 
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