50 SILKWORMS. 



caterpillars in general is that they need to be so closely im- 

 prisoned to check their erratic habits, and they will frequently 

 make persistent and untiring efforts to escape from confinement, 

 and exhibit the greatest ingenuity in finding out the weakest 

 points in their prison walls and making their exit thereat, to the 

 great chagrin of their owner when he finds his treasures fled. But 

 silkworms, fortunately for their possessors, need no such close 

 guarding, and never manifest the slightest tendency to wander 

 till the "mounting' season arrives. In its wild state no doubt 

 the silkworm was as fond of wandering as other caterpillars, but it 

 has lost all its spirit of enterprise during the long generations of 

 luxurious life in which it has not had to provide for its own wants, 

 but has been well fed and well tended by human kind. 



Then again, it is a most remarkable thing that the moths, 

 though possessed of fully formed wings seem either completely 

 devoid of the power of using them for flight, or totally ignorant 

 of the method of doing so. They have plenty of muscles to move 

 them with, but the utmost they can do is to make a rapid 

 fluttering or fanning motion with them, which is wholly insufficient 

 to raise themselves from the ground It is incredible that this 

 should have been the case in their wild condition. It is true 

 there are many Lepidoptera which in the native state do not fly, 

 but in such instances, it is usually only the female that behaves 

 thus, and she has either no wings at all, or only very rudimentary 

 ones, while our silkworm moth has these organs fully formed in 

 both sexes. Moreover, Bombyx mori belongs to a section of 

 Lepidoptera, some members of which, the males especially, are 

 exceedingly powerful and rapid fliers. It is said that if silkworms 

 be reared in the open air for a few generations, they recover the 

 power of flight, a further proof that it is the artificial conditions 

 under which they are now reared that has deprived them of the 

 muscular energy and vigour which once, no doubt, characterised 

 them. 



In all probability, too, the pale, sickly hue of the caterpillar is 

 another result of long domestication. The original stock seems 

 to have had dark brown larvae, and in every large batch there 

 appear a few individuals which preserve to some extent this 

 ancestral characteristic, and appear as dark brown or blackish 

 brindled. These are what the French call " vers tigres " or " vers 

 zebres." Captain Hutton, some years ago, made many experi- 

 ments with these dark forms, and endeavoured to obtain from 

 them a race possessed of the original appearance. He selected 

 ail the dark worms from a batch, and reared them apart from the 

 rest, allowing the moths to couple amongst themselves only. By 



