160 ON REARING SILK WORMS, 



cocoons are of a description one third lighter than the 

 others. When the first are occupied in making their co- 

 coons, the others have already changed into butterflies, and 

 have laid new eggs ; which permits a second raising, that 

 is to say : to employ those eggs in rearing a second crop, 

 the same year. 



(The Chinese author adds in a note that the chrysalides 

 of the late silk worms, must not be eaten.) 



When the leaves covered with the eggs of the silk worms 

 are washed according to the three customary methods, care 

 must be taken to note the manner each leaf has been treated, 

 for if a mistake occurs, or if, for example, the eggs that 

 have been exposed to the dew, be soaked in salt water, all 

 the eggs will become empty and steril. 



Only two colors are distinguishable in cocoons : white 

 a'nd yellow. The country of Tchouen-cken, and that of 

 Tsin-iu, only furnish yellow cocoons without any mixture 

 of white ; the districts of Kia and of Hou, only furnish 

 white cocoons without any mixture of yellow. 



If a white male moth copulates with a yellow female, the 

 silk worms hatched from that union will form a cocoon 

 which will participate of those two colors* 



The yellow silk* can be whitened by washing it, and 

 having it soaked in lard taken from pork kidneys ; but 

 there are two colors which the dyers cannot make it take : 

 one is called piao-pe, (a greenish white color, like that of 

 the fruit of the pear or almond tree,) and peach blossom 

 color. 



Cocoons are of various forms. The cocoons of the late 

 silk worms, (worms of Autumn,) resemble a long gourd, 



\%J? 



* M. Darcet has bleached some yellow cocoons by means of pork fat. (St J.) 



