232 



THE INSECT WORLD. 



At the second age they still cut the leaves for the worms, but 

 into larger pieces, and proportioned to their size. During the day 

 the temperature of the room ought to be kept to 21" Centigrade, 

 but it may be lowered by i^ or 2° during the night. Towards the 



Fig. 211. — Lozenge-shaped net. 



Fig. 212. — Square net. 



end of this age they have only four meals. When the worms are on 

 the point of going to sleep, their meals are decreased. 



During the third age the number of the meals is kept to four, the 

 first being given towards five o'clock in the morning, and the last 

 between ten and eleven o'clock at night. The leaf is cut into much 

 larger pieces, and distributed as equally as possible. The dclitcmcnt 

 and the dedonblenient are proceeded with as in the preceding age. One 

 begins to find pretty often during this period of the life of worms, 

 some hiiseties — that is to say, worms which have not strength enough 

 to moult. They are larger than those just woke up, and that have 

 not as yet eaten, and are shiny. They must be carefully removed, 

 for they will not be long before they die, and infect the air of the 

 room. 



During the fourth age they no longer cut the leaves, but giv( 

 them a great deal more at once. The result is that the litters increase 

 in thickness, and that the dclitemeni must be performed oftener ; foi 

 the rest, four meals are always necessary. Many htiscttes may be seer 

 during the fourth age. The moult which follows the fourth age i; 

 the most critical phase in the life of the silkworm. During thei 

 sleep they are a prey to acute suffering, and are plunged into a state 



