23 



now be transferred to a larger room to complete the rearing. Care 

 must be taken to heat this room the day before to 80° F. , and the next 

 day lower the heat to the degree adopted for the rearing. Feed six 

 times daily either with whole leaves or leaves which are coarsely cut 

 up. For this as well as all the other ages the best rule to follow in 

 feeding is to give only a light sprinkling of leaf at the beginning and 

 end of each age, gradually increasing the ration up to the middle of 

 each age, and then diminishing to the time of a molt. The appetite 

 of the worm will serve as a guide. Give more or less leaf according 

 as the preceding meal has been more or less eaten. In this way leaf 

 will not be wasted and a large quantity of litter will not accumulate 

 under the worms, to their detriment. 



Toward the sixth or seventh day of the third age, according to the 

 temperature, the worms begin to be languid and lose appetite, as 

 before, and are ready to make a third change. This is the most diffi- 

 cult of all and the one in which they seem to suffer the most. It is 

 also the period when diseases due to bad eggs or to a poor incubation 

 are developed. Excepting accidental diseases, a good result may gen- 

 erally be predicted if the third change is safely passed. With these 

 facts in view, from the beginning of the third age keep the worms 

 sparse on the shelves and see that the beds are dry and changed with 

 scrupulous care, the litter being far removed from the rearing room. 

 Avoid feeding with wet leaf, and to favor the molting raise the tem- 

 perature a degree. It will be noticed that the head and body of the 

 worm are more swollen than in other molts. It is this superabundance 

 of liquid that renders this molt so critical and necessitates a drier 

 atmosphere and a bed which is very dry and not apt to ferment. 



The worms increase three times in volume after the third molt, and 

 must have space accordingly. They must be separated into three 

 divisions in the following manner: Instead of waiting, as in the first 

 two changes, until half of the worms have begun to molt, let down the 

 nets, or otherwise prepare for the removal of the backward worms 

 when one-third or even less of the worms show signs of molting. 

 About two-thirds will then crawl up on the fresh leaves, and must be 

 placed on a shelf where, after one or two meals, they proceed to molt, 

 being again divided after the first or second distribution of leaves, 

 according to the rapidity of the molting. 



If only a few worms mount when the first division is made, the oper- 

 ation was delayed too long, and it is unnecessary to divide those first 

 taken up; butafter the change the division of those left on the old bed 

 can be made. To allow the worms to spread out, each division should 

 occupy but one-third of the shelf on which it is placed. 



THE FOTTRTH AGE. 



When all the worms have molted the third time a change of beds 

 must be made as in preceding ages. Do not be in haste to change. 



165 



