Htf 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, the caterpillar draws 

 the pedicles closely together with ligaments of silk, 

 and thus provides for itself a pretty secure lodge- 

 ment in the interior. 



The larvae which follow the modes of architecture 

 hitherto described, spend their lives in solitude, 

 each confining himself to his own 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 obtain 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 (Porthesia Chrysorrhcea}, 

 whose nests may be taken as an example of the 



