230 MOTH. 



But of all the Moths of the tribe Bombyx the 

 Phalcena Mori or Silkworm Moth is by far the 

 most important. This is a whitish Moth, with a 

 broad pale-brown bar across each of the upper 

 wings. The caterpillar or larva, emphatically 

 known by the title of the Silkworm, is, when full 

 grown, nearly three inches long, and of a yellow- 

 ish grey colour: on the upper part of the last 

 joint of the body is a horn-like process, as in 

 many of the Sphinges. It feeds, as every one knows, 

 on the leaves of the white Mulberry, in defect of 

 which may be substituted the black Mulberry, 

 and even, in some instances, the Lettuce and a 

 few other plants. The Silkworm remains in its 

 larva state about six weeks, changing its skin four 

 times during that period, and, like other cater- 

 pillars, abstaining from food for some time before 

 each change. When full grown the animal en- 

 tirely ceases to feed, and begins to form itself a 

 loose envelopement of silken fibres in some con- 

 venient spot which it has chosen for that purpose, 

 and afterwards proceeds to enwrap itself in a 

 much closer covering, forming an oval yellow 

 silken case or ball about the size of a pigeon's 

 egg, in which it changes to a chrysalis, and after 

 lying thus inclosed for the space of about fifteen 

 days, gives birth to the Moth. This however is 

 always carefully prevented when the animals are 

 reared for the purpose of commerce, the Moth 

 greatly injuring the silk of the ball by discharging 

 a quantity of coloured fluid before it leaves the 

 cell : the silk-balls are therefore exposed to sach a 



