LEPIDOPTEROUS INSECTS. 



THE present order contains only three tribes; the 

 Sphinges and Moths. These are all produced from caterpillars, by a 

 ehange that is common to all the insect species. The caterpillars pro- 

 ceed from eggs ; and the eggs of Butterflies are sometimes so numerous, 

 that, in the spring of the year, the leaves and tenderest stems of plants 

 are nearly covered with them. 



Caterpillars are, in general, extremely voracious. Some of them 

 eat more than double their own weight in a day, and this without 

 suffering any inconvenience; for the digestive powers of all animals 

 are proportioned not so much to their size, as to the duration of their 

 lives. 



They often change their skin without much altering their shape, 

 till at last they assume a shape very different from that which they 

 before possessed. They have now the name of Aurelia or Chrysalis ; 

 and in this state all the parts of their future form are visible, but 

 under a thick shell : and these are so very soft and delicate, that the 

 least touch discomposes them. 



The production and manners of these animals, afford subject both 

 of amusement and instruction. 



About the middle of summer a butterfly deposits from three to four 

 hundred eggs on the leaf of a tree ; from each of these, in a few days, 

 a young caterpillar proceeds. The eggs of one of the species are no 

 sooner hatched, than the young-ones begin to form a common habita- 

 tion. They spin silken threads, which they attach to one edge of the 

 leaf and extend to the other. By this operation they make the two 

 edges of the leaf approach each other, and form a cavity resembling a 

 hammock. In a short time the concave leaf is completely roofed with 

 a covering of silk. Under this tent the animals live together. 



About the beginning of October, or when the frost commences, 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 symptoms of life, and begin to creep. 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 

 .creatures know how to enlarge both the nest and its passages, by 

 additional operations accommodated to their present state. Into these 

 new lodgings they retire, in order to screen themselves from the 

 Injuries of the weather, or to cast their skins. In fine, after having 

 east their skins several times, the r>eriod of their dispersion arrives. 



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