20 BUTTERFLIES 



for survival through the winter. The most conspicuous 

 examples are the Swallowtails, nearly all of which hiber- 

 nate in the chrysalis stage. Other examples are the va- 

 rious Whites, the Orange-tips, and isolated species like 

 the Wanderer, and the Spring Azure and the American 

 Copper. Practically all the butterflies that pass the 

 winter as chrysalids have a silken loop running around near 

 the middle of the body which helps to hold them securely 

 through the long winter months. Apparently none of 

 those chrysalids which hang straight downward are able to 

 survive the winter. 



An adult butterfly seems a fragile creature to endure the 

 long cold months of arctic regions. Yet many of our most 

 beautiful species habitually hibernate as adults, finding 

 shelter in such situations as hollow trees, the crevices in 

 rocks, the openings beneath loose bark or even the outer 

 bark on the under side of a large branch. It is significant 

 that most of the adult- wintering Angle- wings are northern 

 rather than southern species, some of them being found in 

 arctic regions practically around the world. One of the 

 few southern forms that hibernates as an adult is the Goat- 

 weed Emperor. (See plate, page 209.) 



These examples are all cases of true hibernation in a 

 lethargic condition. There are certain butterflies, how- 

 ever, which pass the winter as adults that remain active 

 during this period. Obviously this is impossible in lati- 

 tudes where the winter is severe, and it involves migration 

 to a warmer climate. The one notable illustration of this 

 is the Monarch butterfly which apparently flies southward 

 to the Gulf states at least and there remains until spring, 

 when individuals come north again. The southward mi- 

 gration may be begun in Canada when the butterflies 



