SILK-WORMS. 
11 
deposited in an egg, in order that at the time of 
their developement in fine weather, they may im- 
mediately find proper nourishment at hand: other 
kinds, born in autumn, and consequently small, 
envelop themselves in many leaves, or other ve- 
getable substances, which they unite, arrange and 
attach with great skill, by means of thin silken 
threads ; here they live in a torpid state, to come 
forth when the leaf unfolds itself: we see also 
some species preserve themselves under the form 
of nympha , or chrysalis, in various kinds of co- 
coons or retreats: others again lodge themselves in 
the ground, on walls, in the trunks of trees, under 
stones, &c., waiting for the mild and warm season. 
During winter, we meet everywhere with eggs 
or caterpillars, or chrysalides, attached or sus- 
pended from trees, or fixed to walls, in the fields, 
meadows, woods, &c., and always as much as 
possible sheltered from cold and other inclemen- 
cies, of the season. We often see also in the 
■winter, in the meadows, marks which point out 
the nest of some kind of caterpillar. 
As soon as fine weather appears, the caterpillar 
emerges suddenly from the egg, develops itself, 
changes into a chrysalis in the cocoon, and at 
last appears in the form of a butterfly. 
Among the different kinds of caterpillars, there 
are some which live entirely apart ; others which 
live together till the first casting of their skin, or 
