154 



THE INSECT WORLD. 



Another species uses its hairs in the composition of its cocoon ; 

 but it adopts an entirely pecuHar way of tearing them out, when the 

 tissue of its cocoon has become a species of network of pretty closely 

 packed rings. Reaumur one day saw one part of the cocoon 

 bristling with hairs. These were the hairs of a part of the back of 



the caterpillar, which it had pushed 

 through the rings of its cocoon. 

 The caterpillar then moved about 

 as if rubbing this part of its back 

 successively in opposite directions 

 against the interior surface of the 

 cocoon. In this way the hairs were 

 very soon torn out and kept retained 

 in the rings of the cocoon. This 

 cocoon is then bristly inside, and 

 does not at all suit the future 

 chrysalis, which does not like to be 

 touched by any but smooth sur- 

 faces. The caterpillar then works 

 with its head, to lay the hairs along 

 the interior surface, and to keep 

 them down by threads, which it 

 draws over them. At another time Reaumur saw a small hairy 

 caterpillar, which appeared to live on lichens, using its hair in another 

 way. It tore them out to make its cocoon, but it was not to lay 

 them down and work them into a tissue. It set them straight up 



Fig. 117. 

 Larva of Chelonia caja forming its cocoon. 



Small Caterpillar of the Pimpernel. 



Fig. 119.— Cocoon of the same. 



like the stakes of palisades, On the circumference of an oval space 

 in which it was placed. Shut up within this palisade, it spun a ligh 

 white web. This web supports the hairs, causing the greater part 



