234 THE INSECT WORLD. 
by M. Eugéne Robert. These are leaves of paper, of a peculiar 
manufacture, pierced with holes proportioned to the size of the 
worms which are to pass through them. The paper net can be 
used advantageously also for separating the worms that are too 
near together, or, as they say, for the dédoublement. Formerly, 
the délitement and the dédoublement were done by hand—a tedious 
work, and one that presented serious disadvantages. Now-a-days, 
as we have seen, the worms themselves perform these two perilous 
operations. 
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° Cen- 
tigrade, but it may be lowered by 1° or 2° during the night. 
Towards the 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 deélitement and the dédoublement are proceeded with as in the 
preceding age. One begins to find pretty often during this period — 
of the life of worms, some (uisettes—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 give 
them a great deal more at once. The result is that the litters 
increase in thickness, and that the délitement must be performed 
oftener ; for the rest, four meals are always necessary. Many 
luisettes may be seen during the fourth age. The moult which 
follows the fourth age is the most critical phase in the life of the 
silkworm. During their sleep they are a prey to acute suffering, 
and are plunged into a state of lethargy which resembles death. 
The dryest and cleanest litters diffuse very soon a sickly smell. 
This moult lasts from thirty-six to forty-eight hours. During 
this time the room should be kept to at least 22° Centigrade. 
SS a ee es 
