284 
THE STUDY OF INSECTS . 
mens the white predominates; other specimens are almost 
entirely black, excepting the spear-mark. According to Eu¬ 
ropean authorities the larva is brown or blackish brown, with 
a darker line along the middle of the back, and a row of horse- 
shoe-shaped spots on the sides. It feeds on birch and sweet 
gale. It is gregarious, a colony of larvae spinning together 
the leaves of the food-plant, and thus forming a nest within 
which they live and feed. The 
larva has not yet been observed 
in this country. 
The Scallop - shell Moth, 
Calocalpe undulata (Cal-o-cal'pe 
un-du-la'ta).—This is a pretty 
Fig. 336 .—Calocalpe undulata. 
moth, with its yellow wings 
crossed by so many fine, zigzag, 
dark brown lines that it is hard 
to tell which of the two is the 
ground-color (Fig. 336). It 
lays its eggs in a cluster on 
a leaf near the tip of a twig 
of cherry, usually wild cherry. 
The larvae make a snug nest 
by fastening together the leaves 
at the end of the twig; and 
within this nest (Fig. 337) they 
live, adding new leaves to the 
outside as more food is needed. 
The leaves die and become brown, and thus render the nest 
conspicuous. The larvae are black above, with four white 
Fig. 337.—Eggs and nest of Calocalpe 
undulata. 
