CLASS INSECTS. 391 



The nourishment of the silkworm consists in the leaves of 

 the mulberry (Fig. 371), and it is consequently on the cul- 

 ture of this plant that the possibility of rearing these insects 

 depends. The white mulberry is the species most generally 

 employed for this purpose ; it is a tree which grows to the 

 height of forty or fifty feet, and which gives four or five 

 quintals* of leaves, sometimes even ten or twelve. It accom- 

 modates itself sufficiently well in most localities, and it has 

 been cultivated with success even in the north of Europe, 



Fig. 371. Silkworm. 



but it grows nowhere wild. In fact, this mulberry-tree is 

 originally from China. Two Greek monks introduced it into 

 Europe towards the middle of the sixth era, and the silk- 

 worm with it.f Its culture soon spread throughout the 



* Quintal, one hundred pounds weight. 



t " I need not explain that silk is originally spun from the bowels of a 

 caterpillar, and that it composes the golden tomb from whence a worm 

 emerges in the form of a butterfly. Till the reign of Justinian, the silk- 

 worms, who feed on the leaves of the white mulberry tree, were confined to 

 China ; those of the pine, the oak, and the ash, were common in the forests 

 both of Asia and Europe, but as their education is more difficult, and their 

 produce more uncertain, they were generally neglected, except in the little 

 island of Leos, near the coast of Africa. A thin gauze was procured from 

 their webs ; and this Leon manufacture, the invention of a woman, for female 

 use, was long admired both in the East and at Rome. Whatever suspicions 

 may be raised by the garments of the Medes and Assyrians, Virgil is the 

 most ancient writer who expressly mentions the soft wool which was combed 

 from the trees of the Seres or Chinese ; and this natural error, less mar- 

 vellous than the truth, was slowly corrected by the knowledge of a valuable 

 insect, the first artificer of the luxury of nations. That rare and elegant 



