SOCIETY OF ANIMALS. 245 



and all the injuries of the air, during eight or nine months. 

 About the beginning of October, or when the frost first com- 

 mences, the whole community shut themselves up in the nest 

 During the winter they remain immovable, and seemingly 

 dead. But, when exposed to heat, they soon discover symp- 

 toms of life, and begin to creep. In this country, they seldom 

 go out of the nest till the middle or end of April. When 

 they shut themselves up for the winter, they are very small ; 

 but, after they have fed for some days in spring upon the 

 young and tender leaves, they find the nest itself, and all the 

 entrances to it, too small for the increased size of their bodies. 

 To remedy this inconvenience, these disgusting reptiles know 

 how to enlarge both the nest and its passages by additional 

 operations accommodated to their present state. Into these 

 new lodgings they retire when they want to repose, to screen 

 themselves from the injuries of the weather, or to cast their 

 skins. In fine, after casting their skins several times, the 

 time of their dispersion arrives. From the beginning to near 

 the end of June, they lead a solitary life. Their social dis- 

 position is no longer felt. Each of them spins a pod of coarse 

 brownish silk. In a few days they are changed into chrysa- 

 lids ; and, in eighteen or twenty days more, they are trans- 

 Tor med into butterflies. 



Caterpillars of another species, which Reaumur distin- 

 guishes by the appellation of the processionary caterpillars, 

 live in society till their transformation into flies. These 

 caterpillars are of the hairy kind, and are of a reddish color. 

 They inhabit the oak, and feed upon its leaves. When very 

 young, they have no fixed or general habitation. But, after 

 they have acquired about one half of their natural size, they 

 assemble together, and construct a nest sufficient to accom- 

 modate the whole. The nests of these caterpillars are at- 

 tached to the trunks of the oak, and are situated sometimes 

 near the earth, and sometimes seven or eight feet above its 

 surface. They consist of different strata, or layers of silk, 

 which are spun by the united labor of the whole community 

 Their figure is neither striking nor uniform. On the part of 

 the oak to which they are fixed, they form a protuberance 

 similar to those knots which are seen upon trees. This pro- 

 tuberance sometimes resembles a segment of a circle, and 

 sometimes it is three or four times longer than it is broad. 

 Some of these nests are from eighteen to twenty inches long, 

 and from five to six inches wide. About the middle of their 

 convexity, they often rise more than four inches above the 

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