404 



HABITATIONS OP INSECTS. 



constructing this new habitation, they spin a close silken web 

 round the end of two or three adjoining twigs and the leaves 

 attached to them, so as to include the requisite space. They 

 are not curious in giving any particular form to the edifice : 

 sometimes it is flat, often roundish, but always more or less 

 angular. The interior is divided by partitions of silk into se- 

 veral irregular apartments, to each of which there is purposely 

 left an appropriate door. Within these the caterpillars retire 

 at night, or in rainy weather, quitting the nest on fine days, 

 and dispersing themselves over the neighbouring leaves, upon 

 which they feed. Here, too, they repose during the critical 

 period of the change of their skins. On the approach of win- 

 ter the whole community shut themselves up in the nest, 

 which, by the addition of repeated layers of silk, has at this 

 time become so thick and strong as to be impervious to the 

 wind and rain. They remain in a state of torpidity during 

 the cold months, but towards the beginning of April are 

 awakened to activity by the genial breath of spring, and 

 begin to feed with greediness upon the young leaves that sur- 

 round their habitation, which, as they soon greatly increase in 

 size, 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 inhabitants, as if to 

 guard against such an accident, have gnawed ofi" all the buds 

 within their dwelling, and thus secured themselves from this 

 inconvenience.^ 



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

 Cnethocampa processionea, unfortunately not a native of this 

 country, to which, on account of their singular manners, that 

 will be detailed to you in a subsequent letter, Reaumur has 

 given the title of processionary caterpillars, is somewhat dif- 

 ferent in its construction from that just described, though 

 formed of the same material. As the caterpillars Avhich fa- 

 bricate 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 considerable height from the ground. In shajDe 

 it resembles an irregular knob or protuberance, and the silk 



I Rcauin. li. 12S. 



