REARING SILKWORMS. 11 



relapse into a comatose state and wake to the 

 third age. 



In about the same time the silkworm sleeps its 

 third sleep, and awakes to the fourth age of its 

 brief life, to eat more and grow faster. In this 

 age tha-^e^arWt5frrtation of the worm is more 

 easily studied. They require much more room, 

 as well as food. 



The next molt is the most critical period in 

 silkworm life, and in countries where diseases 

 rage, the silk-raisers are most anxious, as at this 

 time they are sometimes liable to lose almost 

 their entire crop through disease; for then, if any 

 latent infectious disease has been lurking in them, 

 it is sure to manifest itself. 



In the fourth molt the worms are a very inter- 

 esting study, as then they are large enough to 

 permit of close observation of eve^y^jnovem^nt, 

 especially with the aid of a magnifier. When in 

 the act of molting they become rigid. The head- 

 covering becomes loose, and sometimes drops off 

 before they are free from the old skin of the body; 

 but it more often holds on by a single thread or 

 bit of the shell until after the worms are entirely 

 free. Sometimes it remains, hanging loosely, for 

 a good while. Nature is very wonderful in all 

 her works, in nothing more than in the sil^- 

 wornl. As the labor of molting goes on, the old 



