STATE AGRICULTURAL SOCIETY. 
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worms poured out of the nest again and commenced eating, vora¬ 
ciously. And invariably upon very warm days these caterpillars 
eat much more ravenously than at other times. Two or three 
days of hot weather, such as frequently occur about the time of 
planting corn, give them greedy appetites and cause them to 
advance rapidly in size. 
The tent or nest, which is always placed in the fork of a limb, 
is enlarged from time to time, until it becomes from eight inches 
to a foot in diameter. It is composed of a number of sheets or 
layers formed of silken threads woven closely together like dense 
cob-webs. These sheets are placed parallel to each other, and 
at such distances apart as enable the worms to crawl between 
them to repose, the spaces being much narrower between the 
inner layers, formed when the worms were small, than between 
the outer ones. The nest thus resembles the several sheets, 
blankets and other coverings upon a bed, separated sufficiently 
to receive a row of sleeping persons between each of them. As 
eacli new layer which is added to the structure is exactly pa¬ 
rallel with the one below it, presenting the same elevations and 
hollows, it was formerly a query in my mind how the worms 
were able to place the first threads of these layers, for a scaffold¬ 
ing on which to walk to complete the tissue. But, like many 
other phenomena in nature which are a mystery to us at first, 
this becomes quite simple when fully observed. The caterpillars 
as already stated, repose in serene weather on the outer surface 
of the nest, lying, side by side as compactly as they can stow 
themselves. Straggling individuals coming in from feeding at 
this time, to spin their threads upon the surface of the nest, and 
finding it covered to a greater or less extent by their slumbering 
comrades, proceed with their work as usual, traveling over the 
hacks of the reposing caterpillars to and fro in every direction, 
thus spreading a blanket upon them as it were. These caterpil¬ 
lars on awakening from repose, in order to make their exit, 
crowd the thin threads aside in two or three places, thus form¬ 
ing round holes through the web, which thenceforth become the 
doors through which they pass in and out of the new apartment. 
The old portions of the nest become foul, being filled with the 
shrivelled cast skins and black grains exoreted by the worms. 
