CH. XV.] THE CATERPILLAR 253 



which compose their covering 1 . It is singular that 

 these substances should be digested by them ; and 

 still more singular that their colour should be so 

 little affected b)^ this digestive process ; for the ex- 

 crements of these caterpillars are invariably found 

 to be of the same colour (though lighter) as the 

 substances which they may have eaten. 



These caterpillars make short excursions : when 

 the part in which they first settled has been shaven 

 quite bare, the animals remove to another spot in 

 search of a fresh supply. Those which settle upon 

 garments of fur do not like to walk over long hairs ; 





they therefore never proceed except scythe in hand, 

 and cut off every pile which comes in their way. 

 Now and then they are seen in a state of repose ; 

 they then fix their case to the body of the cloth with 

 little threads, and thus, as it were, come to an an- 

 chor. They fix themselves still more firmly to the 

 cloth, when about to fall into a torpid state during 

 the winter, or when about to undergo their meta- 

 morphosis ; they then close exactly both the ends of 

 their case with silken threads, in order that they 



