56 SOCIAL HABITATIONS. 
of the Peacock and SmaLL TorToIsE-SHELL BUTTERFLIES. 
Great black masses of these caterpillars may be seen upon 
the nettles, and, on examining them closely, they will be 
seen to reside within a common home, made of tough 
silken threads, very loosely spun, and forming a kind of 
net, with long and irregular meshes. 
