THE SILKWORM. 33I 



somewhat more than an inch in length, and two lines 

 in thickness. It then feeds, during five days, with a 

 most voracious appetite, after which it 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 

 its coccoon, 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 be- 

 tween 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 coc- 

 coon. They generally remain in this state about 

 forty-seven days. 



The retreat that they thus form is a cone or ball 

 of silk, spun from two longish bags that lie above 

 the intestines, and are filled with a gummy fluid of 

 a marigold colour. The apparatus with which the 

 animal is furnished for spinning the silky threads 

 that principally compose this bag resembles, in some 

 measure, a wire-drawer's machine, in which gold or 

 silver threads are drawn to any degree ot fineness j 

 and through this the animal draws its thread with 

 great assiduity. As every thread proceeds from two 

 gum-bags, it is probable that each supplies its own; 

 which, however, are united as they proceed from 

 the animal's body. If we examine the thread with 

 a microscope, it will be found flattened on one side, 

 and grooved along its whole length. Hence we may 

 infer that it is doubled just upon its leaving the 

 body, and that the two threads stick to each other 

 . by the gummy quality they possess. 



