14 
THE ART OF REARING 
tion. Others, placing the threads between the 
twigs or small branches of trees, drawing their 
silk, strive with industry to shelter the chrysalis. 
It is admirable to observe the art which the vari- 
ous species of caterpillars employ to form the 
silken habitation that is to harbour the chrysalis. 
This art is the more ingenious, because some of 
the species have less silk than the others. Some 
are obliged to penetrate into the earth to screen 
their retreats. Others, to unite with their silk 
various substances, such as hair, and bits of 
leaves, &c. &c. In short, this little animal does 
all it can to build itself a retreat which may pro- 
tect it from the rigours of the seasons, at the mo- 
ment of its change to the state of chrysalis. 
The period caterpillars employ in the spinning 
of their silk, and consequently in the construction 
of their habitation, varies. Some there are that 
construct them in an hour, others in a day, others 
in two days ; and the silk-worm generally takes 
three days to spin the cocoon. 
The quantity of silk which caterpillars com- 
monly produce, is not always in proportion to their 
size. The silk-worm, which is not of the largest 
species, produces more silk than any of the others. 
(Chap. XIV. § 5.) 
There is great variety in the colours of caterpil- 
lars ; we see them of yellow, white, red, brown, sky- 
blue, greenish colours, and various other shades. 
