INTRODUCTION. 
53 
which destroy the property and lives of their less 
powerful companions, butterflies derive their suste- 
nance from the nectareous juices and secretions of 
fruits and flowers. Instead of grovelling on the 
“ dungy earth,” they are generally seen either sport- 
ing in the air, or resting on the disk of some expanded 
flower, and all their habits are such as beseem “ pure 
creatures of the element.” They are seldom noticed 
but in fine weather, and never in profusion but when 
the season is in its highest bloom, and their appear- 
ance thus becomes associated in our minds with the 
charms of external nature, and is connected with 
those images of life and beauty which give rise to 
many of the genial influences of summer. Several 
species also contrive to outlive the winter, although 
their frail forms seem but ill adapted to resist the 
rigours of that inclement season, and issuing from 
their retreats in the first warm days of spring, are 
among the earliest and not least interesting heralds 
of the “ purple year These circumstances, to- 
gether with the very striking manner in which they 
exhibit the phenomena of transformation, have long 
rendered them general favourites, and caused their 
history to be investigated with greater attention than 
* In the sunny clime of Italy, where it may be said that 
nature never dies, and probably also in other southern 
countries of Kurope, most of the species which with us re- 
tire on the approach of winter into the crevices of walls, 
and other sheltered situations, are seen upon the wing 
throughout even the colder months — at least we know that 
it is so with Van. cardui, Atalanta, and a few others. 
