90 
INTEODUCTION. 
in wliicli they pass the winter and continue to dwell 
all the time they remain in society. This they 
generally form near the extremity of some of the 
tTOgs that alforded them food. It presents, -q;hen 
completed, the appearance of a large packet of silk 
and leaves rudely interwoven, and of no imiform 
shape, the latter being regulated entirely by the 
disposition of the shoots which support it. The 
whole colony work busily at this new edifice, and 
stretch their strong nets in all directions till they 
have enclosed a sufficient space. The different 
webs divide the interior of the nest into several 
compartments of very irregular form, but each of 
sufficient capacity to contain a number of caterpil- 
lars. When the interior is laid open, a number of 
cells are visible, forming such a complete labyrinth, 
that it is difficult to comprehend how the larvae that 
lodge in the centre find means to roach their 
quarters. This, however, they are enabled to do 
by means of doors or passages, which they take 
care to leave open at convenient places as the 
structme advances. Tlie texture of these nests is 
so strong that they withstand all the storms of 
winter and spring, and protect then- little inmates 
till the beginning of summer, when they disperse 
in order to imdergo their metamorphosis. 
The nests of other kinds of social caterpillars are 
frequently formed with less art than the above. 
Those found in such profusion in certain seasons 
on apple trees, made by caterpillars which produce a 
small pearl-white moth, sprinkled with black dots, 
