THE LIFE HISTORY. 
7 
corresponding rapid growth in size. In consequence its new coat 
soon becomes too small, and the moulting process is repeated several 
(sometimes five or six) times, with corresponding changes in the size 
of the larva. In many instances there are marked changes in the 
colors and the shape of the caterpillar after each moult. At length, 
in the course of several weeks, the insect arrives at its full growth. 
It now ceases to eat, and looks about for a suitable place in which to 
pass its period of inactivity, known as the pupa or chrysalis state. 
And here, before he spins his cocoon or changes to a pupa, we will 
take a last good look at him. 
The larva of a lepidopterous insect is jointed or segmented into 
thirteen divisions. First comes the head, which is usually hard and 
horny; the eyes, twelve in number, are very small, and are placed 
near the month. They are simple eyes with very convex lenses, so 
that the range of vision must be very short; in fact, so deficient is 
the sight of caterpillars one may conclude that they are guided more 
by the sense of feeling than by sight. Place a caterpillar on a twig 
and watch it ascend, feeling its way and reaching out from side to 
side before every advance movement. When it reaches the top, it 
does not survey the scene below, but taking a firm hold with its last 
turn or three pairs of claspers, it stretches its body out to the utmost, 
swinging first one side and then the other, in order to feel if there is 
anything beyond on which it can lay hold. 
The jaws of a caterpillar move horizontally and are powerful in¬ 
struments, capable in the larger species of biting through the tough 
ribs of leaves as the insect reaches them while feeding. Crawding 
down the midrib of a leaf the caterpillar advances toward the edge, 
and holding the leaf between one or more pairs of its horny front 
legs, it brings its jaws together on opposite sides, cutting out a small 
piece with each bite, and continuing this down with regular order, 
it soon cuts out a large semicircular space, taking ribs and all. A 
smaller caterpillar will simply eat away the soft parts of the leaf be¬ 
tween the small ribs, leaving a skeleton; while the very minute leaf 
miners burrow in the substance of the leaf between the upper and 
lower skin. 
The noise made by a large colony of larvee while feeding has 
been compared to that made by a heavy shower of rain on an attic 
roof; and the quantity of food which they require is well-nigh appal¬ 
ling to a novice who has started perhaps with several hundred tiny 
creatures which could all make a meal on a handful of leaves, and 
