SEASONABLE INSECT STUDIES. 85 
large bunches of glistening white masses, suggestive of a 
dried frothy substance. When broken open these masses 
are seen to contain hundreds of small, .white, spherical eggs, 
held together by the froth-like substance that permeates 
the whole mass. If the cocoon itself be pulled apart there 
will be found within it the empty brown pupa case, from 
which the moth has emerged. 
These are the eggs and cocoons of the white marked 
tussock moth. Should you leave one of these egg masses 
in place and watch it in spring, you would see, sometime 
in May or early June, soon after the leaves develop, hun¬ 
dreds of tiny, hairy caterpillars come forth from the mass, 
and crawl along the bark toward the leaf bearing branches. 
When the latter are reached each caterpillar begins feed¬ 
ing upon the succulent green portions of the leaves. The 
young caterpillars are about one-sixth of an inch long, and 
are thickly covered on the back and sides with dark brown 
hairs. 
At the end of a week from the time of hatching, the lar¬ 
vae, as these caterpillars are often called, shed their skins, 
crawling out in a new covering previously formed beneath 
the old one. They continue feeding soon after this first 
moult, and a week or two later again shed their skins, to 
provide for their increase in size. After another period of 
feeding, a third moult takes place; the caterpillars by this 
time have become nearly an inch long, and are handsome 
creatures, yellow in general color, with brilliant, coral red 
markings. 
About a week after the third moult a large proportion of 
the caterpillars desert the leaves and seek the rough bark 
of the trunk or larger branches where they spin loose, brown¬ 
ish, silken cocoons, within which they transform to the 
pupa or chrysalis stage. These are the caterpillars which 
are to develop into male moths. The other caterpillars re¬ 
main upon the leaves, feeding freely, and undergoing one 
