Spinning Caterpillars. 345 



parts of Britain, is one of these. It selects for its retreat a 

 crack in the bark of the tree upon which it feeds, and over 

 this spins only a few straggling threads. We found last 

 summer (1829), in the hole of an elm-tree in the Park at 

 Brussels, a group of half a dozen of these, that did not seem 

 to have spun any covering at all, but trusted to a curtain of 

 moss (Hypna) which margined the entrance. (J. R.) In a 

 species nearly allied to this, the yellow-tussock (Dasychira 

 pudibunda, STEPHENS), the cocoon, one of which we have 

 now before us, is of a. pretty close texture, and interwoven 

 with the long hairs of the caterpillar itself (see figure 6, page 





Cocoon of Arctia villica. 



Net-work cocoon. 



17), which it plucks out piecemeal during the process of 

 building, as is also done by the vapourer (Orgyia antiqua, 

 HUBNER), and many others. 



These are additional instances of the remarks we formerly 

 made, that caterpillars which spin a slight web are trans- 

 formed into perfect insects in a much shorter period than 

 those which spin more substantial ones. Thus the cream- 

 spot tiger (Arctia, villica, STEPHENS) lies in chrysalis only 

 three weeks, and therefore does not require a strong web. It 

 is figured above, along with another, which is still slighter, 



