UNWINDING THE COCOONS. 45 



proceeding, as above explained, it encloses itself 

 in a cocoon which only consumes as much silk as 

 is necessary to hold the chrysalis." 



The use of the cocoon, in the natural state of 

 the insect, is to afford a warm nest, where, secure 

 from the inclemencies of the season, and the 

 attacks of enemies, it may undergo its final 

 changes. The cocoon is made water-tight by an 

 internal lining of gum, and the silken thread of 

 which the ball is made is also smeared with a 

 similar gum, which hardens in the air. 



While the worm is spinning its cocoon it takes 

 no food, and as it is continually emitting silk, its 

 body gradually diminishes to less than half its 

 original length. When its labour is completed 

 it rests awhile, and then once more throws off 

 its skin ; but it is no longer 

 a caterpillar ; its form is 

 changed into a chrysalis, or 

 aurelia, with a smooth brown 

 skin, and pointed at one end. A few days after 

 the insect has finished spinning, the cocoons will 

 be ready to be unwound. Our amateur silkworm 



THE CHRYSALIS. 



