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THE SECOND AGE. 



The coming out of the molt is announced by the appearance of a 

 small triangular-shaped livid spot on the worm's head, and the changed 

 skin is grayish in color. The worm takes several hours to recover 

 from a change; then it begins to search for food, which, however, as 

 before stated, must not be given before all the worms have recovered 

 from the molt. Then a slight meal is given by means of perforated 

 paper or nets. ' The worms crawl up promptly and can be easily 

 gathered up and placed on fresh shelves. 



If the two sets of worms recover from their molt at the same time, 

 they may be classed together; if there is a difference of a day, it will 

 be necessary to keep them separate throughout the rest of the rear- 

 ing, for the equality of age has disappeared, and, if they are put 

 together, the second change will not occur simultaneously for all the 

 worms, but will extend over several days, and occasion the greatest 

 trouble to reestablish the equality of size necessary for the best results. 



In case no worms have had change of bed before the molt, do not 

 recommence feeding until the greater part of the worms are awake. 

 Do not fear that they will suffer from hunger. Then form a new 

 division of those still molting. It is frequently better to have two 

 divisions, but if, to simplify the work, but one is desired, by putting 

 the backward worms on the highest shelves, and feeding them oftener 

 than the advanced set, an equality may be reestablished. 



Three days after the first molt the beds must be renewed, and at 

 the same time more space must be allowed the worms. 



The second age is the shortest, being less by two or three days than 

 any of the others. Toward the fifth day of this age the worms begin 

 to molt again. Then act as before — that is, by aid of nets or per- 

 forated paper, remove the backward worms, in order to place them 

 elsewhere, and try by more heat and abundant food to make them 

 catch up with the forward worms. 



THE THIB.D AGE. 



When the worms are over their second molt they cease to be gray, 

 and take the characteristic color of their race. If they are too long 

 in molting it is because the temperature is too low; that is, below 68° 

 F. Increasing the heat a few degrees will excite the worms and enable 

 them to complete their change. After this the temperature adopted 

 for the rearing must gradually be resumed. 



The worms double their size in their third age; consequently the 

 space allotted to them must be doubled; that is, they must have 16 

 square yards instead of 8 square yards, as in the second age. 



From the second to the third molt the same care is to be given as 

 has been prescribed for the first two ages, except that, if a small incu- 

 bating room has been used instead of an incubator, the worms must 



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