88 
INTRODUCTION, 
as they sometimes do naturally for the protection of 
the seed, they form a little hollow or cup in the 
middle, a circumstance so well exemplified in the 
wild carrot (Daucus Carota), that it has procured 
for it the name of the bird’s nest. Ingeniously 
availing itself of this tendency, tlie caterpillar draws 
the pedicles closely together with ligaments of silk, 
and thus provides for itself a pretty secure lodge- 
ment in the interior. 
The larvas which follow the modes of arcliitecture 
hitherto described, spend their lives in solitude, 
each confining himself to his oivn leafy tenement, 
as closely as a hermit to his cell. Others, however, 
are of a more social and convivial disposition, and 
not only feed in company, but form tents which are 
common to the whole community. These little 
commonwealths are the offsprings of one mother, 
originating from eggs which she has deposited in 
clusters on the plant best adapted to the nourishment 
of the young. In some cases, as has been already 
mentioned, the latter continue together only for a 
certain time after they are hatched and then separate, 
probably in order to obt.ain a more abundant supply 
of food. But in other instances, it seems essential 
to their economy that they continue to associate 
until they reach their perfect condition. Of the 
former description are the caterpillars, so abundant 
in some years on fruit trees, which produce a moth 
of a beautiful snow-white, with the apex of the 
abdomen bright yellow CPo7'thesia ChrysorrhceaJ, 
whose nests may be taken as an example of the 
