80 FIRST BOOK OF ZOOLOGY. 



rope, and now common in certain parts of 'New England. Its 

 wings are yellow, with two blackish spots on the forward 

 wing, and one on the hinder wing. The chrysalides of this 

 species are very common on fences, and, when collected in 

 the fall, may be kept through the winter. During February 

 and March the butterflies will come out, and these may be 

 fed on honey or sugar mixed with water, and in this way 

 may be kept alive for some time. 



Y5. The caterpillar, then, having changed into the chrys- 

 alis, remains in this condition a few weeks, or even many 

 months, and then the skin slowly cracks open, and out crawls 

 a creature no longer like a caterpillar, but having three pairs 

 of long, jointed legs, the body divided into three very distinct 

 regions the head, thorax, and abdomen the thorax having 

 wings, and the head furnished with long antennae, and pro- 

 vided with mouth-parts suitable for sipping nectar, and no 

 longer like the heavy jaws of the caterpillar, suited only to 

 chewing coarse leaves ; in short, a creature resembling the 

 insect which first laid the eggs from which the caterpillar 

 came. 



76. Other names are given to these three stages of an 

 insect. The worm, or caterpillar, is called the larva; the 

 chrysalis is called the pupa; while the perfect insect is called 

 the imago. These terms are necessary, for without them 

 the proper condition of an insect could not be easily de- 

 scribed. 



Take, for example, the caterpillar stage of a butterfly: 

 the same stage in a common fly is known by the name of 



