LEPIDOPTERA. 163 
its mouth, reduces it to a sort of paste, which it then uses in the 
formation of an envelope, of such hardness that a knife can hardly 
cut into it. 
The Tinea lines the interior of a grain, of which it has 
previously devoured the contents, with a coating of silk, and 
divides it thus into two different chambers. In one of these it 
is to change into a pupa; in the other it places its excrement. 
And so the little careful architect constructs its house in such a 
manner as to find in it tranquillity, cleanliness, and comfort. 
When caterpillars have not within their reach the materials 
they are in the habit of employing, like good workmen, they 
content themselves with what they can get. Réaumur reared a 
caterpillar which formed its cocoon of pieces of the paper of 
which the box was made in which it was imprisoned. 
What an extraordinary condition! what a strange phase of 
vitality does the chrysalis present to us—a being occupying the 
middle state between the caterpillar and the perfectinsect! How 
little does it resemble that which it previously was, and what 
it will become! In appearance it is scarcely a living being; it 
takes no nourishment, and has no digestive organs; can neither 
walk nor drag itself along, and hardly bends the joints of its 
body. ‘The outside skin of the chrysalis appears to be cartila- 
ginous ; it is generally smooth, although some species have hairs 
scattered over their bodies. 
We distinguish in chrysalides two opposite sides. The one is 

Fig. 124.—A conical pupa. Fig. 125.—Pupa having angular projections. 
the insect’s back, the other its under side. On the upper part of the 
latter (Fig. 124) we perceive various raised portions, formed and 
M 2 
