HABITATIONS OF INSECTS. 475 



they find it necessary to enlarge. One might fear that 

 a structure formed of such materials would at this period 

 be sadly damaged by the growth of the young shoots 

 and leaves of the twigs which it incloses ; but the inha- 

 bitants, as if to guard against such an accident, have 

 gnawed off all the buds within their dwelling, and thus 

 secured themselves from this inconvenience*. 



The nest of the larvae of another species of moth, the 

 Lasiocampa proccssionea, unfortunately not u native of 

 this country, to which on account of their singular man- 

 ners, that will be detailed to you in a subsequent letter, 

 Reaumur has given the title o^ processiojiary caterpillars, 

 is somewhat different in its construction from that just 

 described, though formed of the same material. As the 

 caterpillars which fabricate it feed upon the leaves of 

 the oak, it is always found upon this tree, attached not 

 to the branches but the trunk, sometimes at a consi- 

 derable height from the ground. In shape it resembles 

 an irregular knob or protuberance, and the silk which 

 composes it being of a gray colour, at a distance it would 

 be taken for a mass of lichens. Sometimes this nest is 

 upwards of eighteen inches long, and six broad, rising in 

 the middle about four inches from the surface of the tree. 

 Between the trunk and the silken covering, a single hole 

 is left which serves for the entrance and exit of the in- 

 habitants. These differ in their manners from those last 

 mentioned. While very young they have no fixed ha- 

 bitation, contenting themselves with a succession of dif- 

 ferent temporary camps until they have attained two- 

 thirds of their growth. Then it is they unite their labours 



" Reaum. ii. L'^S. 



