LEPIDOPTERA 91 



the legs in the imago. The others are called false or prop 

 legs. The larva is a voracious creature, often eating its 

 own weight of food in a day. Its senses of taste and feel- 

 ing are well developed, but the other senses appear quite 

 rudimentary. Three simple eyes on either side of the head 

 enable it to discern light from darkness. 



The shedding of the skin, called molting, occurs usually 

 four or five times, and in many species the last larval skin 

 forms the cocoon in which transformation to pupa and 

 adult is effected. The larvae of the butterflies never spin 

 cocoons, but those of the moths, with the exception of the 

 ones pupating in the earth, generally form cocoons either 

 from the hair on their bodies or from the secretion of cer- 

 tain glands. The larval state in most species continues 

 one or two months, but in certain species it lasts more than 

 a year. In the pupal stage the insect appears as if dead. 

 Freezing temperature for months does not harm it. The 

 period during which the various species remain in this con- 

 dition is from a few days to a year. The imago of many 

 species takes no food, while in others, such as the hawk 

 moths and some butterflies, it sips nectar or sap through 

 its proboscis formed by the greatly developed maxilla?. 

 The mandibles which chew the food in the larval state are 

 too small for use. 



5. HEMIPTERA 



The members of this order are the true bugs whose mouth 

 parts are adapted for piercing and sucking. They can not 

 bite or chew. Nearly thirty thousand species have been 

 described, and among them are found the greatest enemies 

 of the human race. 



