122 BUTTERFLIES 



ing point for some young observer to determine. Even 

 the eggs take a long time to develop, not hatching for three 

 or four weeks after they are laid. When they do hatch 

 the tiny caterpillars seem not to eat at all but to go di' 

 rectly into hibernation. 



These butterflies are to be found in their preferred habi- 

 tats almost any time during July, August, and September. 

 Apparently many of them live as adults for nearly three 

 months so that whether we consider the egg, the larva, 

 the chrysalis, or the adult we have in this species an unusual 

 duration of life. This is doubtless an adaptation to the 

 fact that the species must get through the year with only 

 one brood. 



This unity of habit with no such variations as occur in 

 many butterflies with a wider range north and south is 

 apparently correlated with the distribution of this butter- 

 fly. It is found in a belt of territory running from New 

 England and the Atlantic states westward at least to 

 Nebraska along a line which approximates the annual 

 isotherm of fifty degrees Fahrenheit. 



The Great Spangled Fritillary 



Argynnis cybele 



To one who wanders much in the woods and open fields 

 there are few summer scenes more characteristic of the 

 season than that of a group of milkweeds in full flower, 

 surrounded by a host of brown butterflies busily sucking 

 the nectar from the curious pink blossoms. There are 

 likely to be several species of these winged creatures, but 

 in many regions of America the largest and most conspicu- 



