LEPIDOPTERA. 



215 



solid object by the posterior and middle portions of its 

 body, as seen in Fig. 1 70, which represents the chrysa- 

 lis {fi) and also the caterpillar [a) of the cabbage-butter- 



Fig. 168, $ 



fly {P. rapcB). This is seen more plainly in Fig. 171, 

 which is the chrysalis of another species of Pieris 

 {P. o/eracea, Harris). The Papilionidae hold the 

 wings erect when at rest, and fly in the daytime. 

 The cabbage-butterfly offers one of the most re- 



Fig. 169, J 



markable and completely recorded examples of insect 

 migrations. It was imported from Europe about the 

 year i860, and finding such favorable conditions here 



