266 
MOTHS AND BUTTERFLIES. 
As soon as the caterpillar is hatched, it spins a little web to cover 
itself, securing the threads all round to the edges of the leaf, so as to 
bend upwards the sides and form a kind of trough, in which it 
remains concealed. One end of the cavity is open, and through this 
the caterpillar thrusts its head while eating. It begins with the 
extremity of the folded leaf, and eats downwards, and, as it gradu¬ 
ally consumes its habitation, it retreats backwards, till at last, 
having, as it were, eaten itself out of house and home, it is forced to 
abandon its imperfect shelter, and construct a new one. This is 
better than the first, for the insect has become larger and stronger, 
and withal more skilful from experience. The sides of the larger 
leaf selected for its new habitation are drawn together by silken 
threads, so that the edges of the leaf meet closely and form a light 
and commodious cavity, which securely shelters and completely con¬ 
ceals the included caterpillar. This in time is eaten like the first, 
and another is formed in like manner. At length the caterpillar 
having eaten up and constructed several dwellings in succession, and 
changed its skin three or four times, comes to its full size, leaves off 
eating and seeks a suitable place in which to undergo its transforma¬ 
tions. The young caterpillars are almost black; the full-grown 
ones measure about one inch and a half, are generally of a brown 
color more or less dotted with white, with a black head, rough with 
elevated white points, with white branching spines on the back, and 
on each side there is a row of yellow crescents. The chrysalis is 
gray, with a whitish bloom upon it like that on a plum, and the 
little pointed tubercles on its back are gold colored. The chrysalis 
state continues about ten days, or longer if the weather be cool and 
wet.” 
The caterpillars of this butterfly are frequently so abundant as to 
almost strip the leaves from the nettles, and being protected as they 
are from the sight of their enemies one would naturally think that 
their chances of life in the struggle for existence were very good. 
However, if a number of the full-grown larvae are collected and ex¬ 
amined, one will soon see the eggs of the ichneumon flies, for these 
parasites have very sharp eyes and even in his curled-leaf home the 
caterpillar of Pyrameis atalanta is not exempt from the fate that 
awaits ninety-nine one-hundredths of his relatives of other species. 
A butterfly having almost a world-wide range is Pyrameis cardui. 
This insect has succeeded in establishing itself over Europe, Asia, a 
good part of North and South America and the Sandwich Islands, 
