30 



times the different ages. The time requisite for the 

 several changes depends greatly on the temperature. 

 If the weather is warm, they will generally happen as 

 follows : the first moulting on the fourth or fifth day after 

 the hatching ; the second begins on the eighth day ; the 

 third on the thirteenth and fourteenth days, and the last 

 change on the twentysecond. 



The fifth age lasts about ten days ; at the end of which 

 the worms have reached their ultimate growth, being 

 three inches in length,* and are prepared to spin their 

 cocoons. Thus thirtytwo days intervene between the 

 hatching and the beginning of the cocoon, and I have 

 known the period retarded to sixty days. These changes 

 will only be noticed by accurate observers. 



FEEDING, CLEARING THE LITTER, ETC. 



Too many leaves should not be given to them at once, 

 and the leaves given should be spread very thin, because 

 if put on too thick, a great nufhberof the worms when 

 small will run the risk of being lost and carried out among 

 the litter. When the worms are in the first age, you need 

 only clean the litter once or twice, as you find it neces- 

 sary. During the whole of the first age, the.leaves of the 

 young plants of the mulberry, as being the tenderest, 

 are preferable to the leaves of older trees for the food of 

 the young worms. It is well therefore to sow some mul- 

 berry seed every year so as to have a succession of young 

 plants. During the temporary sickness produced 



* See Figures, 2, 3, 4, 5, or the different appearance of the in- 

 sect in its different ages. 



