510 Observations on Lisecis. 
is strongly ridged with jaws and teeth, to gnaw and scrape their food, 
to carry burdens, to perforate the earth — ^nay, the hardest wood, and 
even stones, for the habitations and nests of their offspring., n; ■> ';,•/■ i*? 
Nearly all insects (except Spiders, and a few others of iheapterotts 
tribe, which proceed nearly in a perfect state from the egg) undergo 
a metamorphosis, or change, at three different periods of their ex- 
istence. The lives of these minute creaturee, in their perfect state j 
are in general so short, that the parents have seldom; an opportunity 
of seeing their living offspring, consequently they are neither provided 
with milk, like viviparous animals, nor are they, like birds, impelled 
to sit upon their eggs in order to bring their offspring to perfection. 
In place of these, the all-wise Creator has endowed each species with 
the astonishing faculty of being able to discover what substance is 
fitted to afford the food proper for its young ; though such food is, for 
the most part, different from that which the parent itself could eat. 
Some of them attach their eggs to the bark of trees, or place them 
upon the leaves of other vegetable substances ; others drop their eggs 
into the water, an element in which they themselves would soon be 
destroyed. In short, the variety of contrivances that are adopted by 
insects to ensure the subsistence of their offspring, are beyond enu- 
meration. 
From the eggs of all insects, proceed what are called larva, grub?, 
or caterpillars. These consist of a long body, covered with a soft, 
tender skin, di\'ided into segments or rings. In this larvae state, many 
insects remain for months ; others for a year, and some for even two 
or three years. They are in general, extremely voracious, oftentimes 
devouring more than their own weight in twenty-four hours. 
As soon as all their parts become perfected, and they are prepared 
to appear under a new form, called a pupa or chrysalk, most species 
of insects fix upon some convenient place, for the performance of this 
arduous operation. This is generally a place where they are not, 
exposed to danger, for in their transformation they have neither 
strength to resist, nor swiftness to avoid, the attack of an enemy. 
That Power which instructed the parents to deposit their eggs in a 
proper receptacle, directs the offspring to the most secure and appro- 
priate situation for their future defenceless state. Some of them spin 
webs, or cones, in which they enclose themselves; others undergo 
their change in decayed wood; and others conceal themselves beneath 
the surface of the earth. Preparatory to the transformation, they 
cease to take any food, and for some days continue in a state of inac- 
tivity. During this time the internal organs gradually unfold them- 
selves. When the completion is at hand, many of them may be 
observed, alternately, to extend and contract their bodies, in order 
