NATURALIST'S CABINET. 



Colour and size of the eggs Larvae. 



of the most valuable of all insects; affording 

 those delicate and beautiful threads that are after- 

 wards woven into silk, and used in garments in 

 almost all parts of the world. 



These insects are in the warmer climates of 

 the east left at liberty upon the trees, where they 

 are hatched, and on which they form their coc- 

 coons ; but in cooler countries, where these ani- 

 mals have been introduced, they are kept in a 

 room with a south aspect, built for the purpose, 

 and fed every day with fresh leaves. 



Their 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 tender of the mul- 

 berry-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 increased in size, when a second 

 sickness comes on. In the next ten days it ex- 

 periences two other attacks, by which time it has, 



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