OF SOCIABLE CATERPILLARS. 91 



the season is favourable, when they are recalled into 

 action by the genial warmth of the sun, and they 

 quickly crawl abroad, and devastate all the young 

 and tender leaves in the neighbourhood of their 

 domicile. To prevent the possibility of their struc- 

 ture being damaged by the shoots inside, they gnaw 

 all the shoots of leaves off as soon as they are formed. 



By this time the caterpillars increase greatly in 

 size, which obliges them to add to their dwelling. 



The caterpillar of the Processionary Moth (Bombyx 

 processioned) constructs its nest in a different manner 

 from the above, although the materials are the same. 

 These larvae feed universally on the leaves of different 

 species of oak. They always attach their house to 

 the trunk of the tree in place of the branches, and 

 frequently at a considerable height from the ground. 

 It is formed like a large irregular knot, or protuberance, 

 and at a distance is frequently taken for a bunch of 

 lichens, as the colour of the silk of which it is 

 composed is gray. This nest is sometimes eighteen 

 inches in length, and six in breadth, swelling in 

 the centre about four inches from the tree. The 

 ingenious architects leave only a single aperture for 

 their entrance and retreat. In their young state, the 

 Processionary Moth caterpillar differs materially in 

 its habits from that of the Bombyx chrysorrhcea. For, 

 while very young, they have no settled or general 

 habitation ; they content themselves with occupying 

 temporary tents, till they have arrived at above two- 

 thirds of their adult size. They then congregate, 

 and, by their united labours, construct the large 



