INSECTS. 493 
perfect insect of this Caterpillar is found depositing her 
eggs upon the leaves. The heat of the sun soon vivifies 
them and brings forth the Caterpillars, which imme- 
diately proceed to consume the vegetables on which they 
received being. They bear the heat of the sun without 
inconvenience ; but cannot endure long rains; for in wet 
weather they soon disappear. There are several species 
of this butterfly, but the common white, with a black spot 
on each of the under wiugs, is the earliest seen in our gar- 
dens. It lays its eggs in May ; and its Caterpillars, which 
are soon hatched, feed together till the end of June, when 
they go into the pupa state, from which the perfect But- 
terfly appears in July. The eggs laid by the second brood 
of Butterflies produce Caterpillars which feed during the 
remainder of the summer, and remain in the pupa state all 
Avinter, to be hatched the following spring. 
From the astonishing fecundity of these insects, it may 
be wondered that they do not, in the course of time, com- 
pletely overspread the face of the earth, and totally con- 
sume every green plant. This would certainly be the 
case, if Providence had not put a check to their progress. 
One of the kinds of the ichneumon fly deposits her eggs 
within the caterpillar of this Butterfly, and they are there 
hatched. In their larva state they continue preying on 
the vitals of the animal ; they then pass to the pupa 
condition, and eventually emerge the perfect insects. It is 
a fact, that out of thirty individuals of the Cabbage Cater- 
pillar, placed in a glass to feed, twenty-five were pierced 
by the ichneumon, which had totally consumed their in- 
testines. So greatly are we indebted to this apparently 
contemptible little parasite, for keeping down the in- 
crease of an insect, which would otherwise become a sen- 
rious and alarming evil. 
