SILK GROWER'S MANUAL. 163 



third on the thirteenth or fourteenth day, and the last 

 on or about the twenty-second day. 



At each of these critical periods the silkworm remains 

 in a torpid state, eating little, or absolutely nothing, for 

 a day or more. At the end of about ten days from the 

 last period, or in about thirty-two or thirty-four days 

 from the beginning, the insect, now fully grown, is about 

 three or four inches in length, transparent, of a yellow- 

 ish white or pearl color. Having now completed their 

 fifth, or last age, they eat no more, but ascend to the 

 leaves or brushwood which are placed for the purpose, 

 and commence the formation of their cocoons, and in 

 the construction of these the insects work busily and 

 incessantly, night and day, during about four days. This 

 labor finished, the insect in the center becomes trans- 

 formed to the chrysalis state. 



The vitual functions of the silkworm are accelerated 

 by warmth, and the time occupied in passing through 

 the various mutations is hastened, not only by the in- 

 creased temperature, but materially by the degree of 

 attention which is bestowed on the insects. In Madras, 

 according to Dr. Anderson, and where the climate is 

 very warm, the silkworm passes through all its evolu- 

 tions in twenty-two days ; here there is a saving of time 

 as well as of labor, but none in regard to food, as it is 

 admitted the silkworms consume the same amount of 

 cocoons, be the term of their life of a longer or shorter 

 duration. 



The cocoon is usually from an inch to an inch and a 

 half in length, of an oval form, the color yellow or 



