66 NATURAL HISTORY. 
- tribe, from the ufefulnefs of one of the number. The filk worm is 
perhaps, the moft ferviceable of all other animals; fince, from its la¢ 
. bours, and the manufa@ure attending it, near a third part of the worl 
are clothed, adorned, and fupported. 
Caterpillars may be eafily diftinguifhed from worms or maggots, by 
the number of their feet’; and by their producing butterflies or moths. 
When the fun calls up vegetation, and vivifies the various eggs of in- 
_ fees, the caterpillars are the firit that are feen, upon’ almoft every ve- 
getable and tree, eating its leaves, and preparing for a ftate of greatef 
perfection. They have feet both before and behind; which not only 
enable them to move forward by a fort of fieps made by their fore an 
_ hinder parts, but alfo to climb up vegetables, and to ftretch'themfelves 
out from the boughs and ftalks, to reach their food, at a diftance. All 
of this clafs have from eight feet at the leaft, to fixteen; and this may 
ferve to diftinguifh them fvom the worm tribe, that never have fo many- 
The animal into which they are converted, is always a butterfly or 4 
moth’; and thefe are always diftinguithed: from otlier flies, by having 
their wings covered over with a painted duft, which gives them fuch 
various beauty. The wings of flies are tranfparent, as we fee in the 
common fl2th fly ; while thofe of beetles are hard, like hort: from fuch, 
the wing of a butterfly may be eafily diftinguiftied ; and’ words would 
obfeure their differences. 
From hence it appears, that caterpillars, whether in the reptile ftatéy 
er advanced to'their laf ftate of perfection into butterflies, may eafily 
be diftinguifhed from all other infeéts ; being animals peculiarly form* 
ed, and aljo of a peculiar nature. The tranfmutations they undergo 
are alfo more numerous than thofe of any infect hitherto mentioned # 
and, in confequence, they have been placed in the third order of chan- 
ges by Swammerdam, who has thrown fuch lights upon this part 0 
natural hiftory. In the fecond order of changes, mentioned beforey 
we faw the grafshopper and the earwig, when excluded from the eggy 
affume a form very like that which they were after to preferve; an 
feemed arrived at a ftate of perfection, in all refpeéts, except in not ha 
' ving wings; which did not bud forth until they were come to maturity: 
But the infe@ts of this third order, that we are now about to defcribey 
go through a much greater variety of transformations: for, when they 
are excluded from the egg, they affume the form of a fmall caterpillaty 
which feeds and grows larger every day, often changing its fkin, but 
ftill preferving its form. When the animal has come to a certain mag’ 
nitude in this flate, it difcontinues eating, makes itfelf a covering of 
hulk, in which it remains wrapped up, feemingly without life or mo 
tion; and after having for fome time’ continued’ in this fate, it oncé 
more burfts its confinement, and. comes forth a butterfly. Thus we 
fee this animal put on no lef$ than three different appearances, fro™ 
the time it is firt excluded from the egg. It appears a crawling cate 
pillar; then an infenfible aurelia, as it is called, without life or motions 
and laftly, a butterfly, varioufly painted, according to its different kinds 
Having thus diftinguifhed this clafs of infedts from all others, we wea 
fir furvey their hiltory in general; and then enter particularly int? 
the manners and nature of a few of them,. which mof deferve our © 
viofity and-attention. wine 
