THE SILKWORM 



507 



THE SILKWORM, SGGS AND BILK. 



THE SILKWORM. 



The Silkworm is found, in a native state, on mulberry- treoa, in 

 China and some other eastern 

 countries, whence in the reign 

 of the emperor Justinian, it 

 was originally introduced into 

 Europe. It is, however, at this 

 time become, in a commercial 

 view, one of the most valuable 

 of all insects; affording those 

 delicate and beautiful threads, 

 that are afterwards woven into 

 silk and manufactured into gar- 

 ments 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 cocoons: 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 are 

 fed every day with fresh leaves. 



The eggs are of a straw-color, 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 color eight or nine days. The 

 worms are put on wicker shelves, covered first with paper, and on this 

 with a bed of the most tender of the mulberry-leaves. Several ranges 

 are placed in the same chamber, one above another, 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 con- 

 tinues feeding during eight days after its birth, when it becomes about 

 the 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 increased 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 some- 

 what more than an inch in length, and two lines in thickness. It then 

 feeds during five days, with a most voracious appetite; after which U 

 refuses food, becomes transparent, with a tinge of yellow, and leaves 

 its silky traces on the leaves that it passes over. These signs denote 

 that it is ready to begin the cocoon, in which it is to undergo its change 

 into a chrysalis. The animals are then furnished with little bushes 

 of heath or broom, stuck upright between the shelves ; they climb up 

 the twigs, where, after a little while, they begin the foundation of 

 their lodge, and are five days in spinning the cocoon. They generally 

 remain in this state about forty -seven days. 



