33O THE SILKWORM. 



Into Europe in the reign or the emperor Justinian. 

 It is, however, at this time become, in a commercial 

 view, one of the most valuable of all insects ; afford- 

 ing those delicate and beautitul threads that are af- 

 terwards woven into silk, and used in garments in 

 almost all parts of the world. 



In the warmer climates of the East the Silkworms 

 are left at liberty upon the trees, where they are 

 hatched, and on which they form their coccoons ; 

 but in cooler countries, where these animals have 

 been introduced, they are kept in a room with a 

 south aspect, built for the purpose, and fed every 

 day with fresh leaves. 



The eggs are of a straw-colour, and each about 

 the size of a pin's head. At its birth the larva or 

 worm is entirely black, and about as long as a small 

 ant ; and it retains this colour eight or nine days. 

 The worms are put on wicker shelves, covered first 

 with paper, and on this with a bed of the most ten- 

 der of the mulberry-leaves. Several ranges are 

 placed, one above another, in the same chamber, 

 about a foot and a half apart. The scaffolding for 

 these ranges should, however, be in the middle of the 

 room, and the shelves not too deep. The worm 

 continues feeding during eight days after its birth, 

 when it becomes about a fourth of an inch in 

 length : it then experiences a kind of lethargic sleep 

 for three days, during which it casts its skin. It 

 now feeds for about five days, and is considerably in- 

 creased in size, when a second sickness comes on. 

 In the next ten days it experiences two other attacks, 

 by which time it has attained its full growth, and is 



