274 BUTTERFLIES 



is not improbable that some of the caterpillars of the first 

 brood remain unchanged throughout the season, so that 

 the insect is both single- and double-brooded in the same 

 locality. 



The Yearly Cycle 



The yearly cycle in southern New Hampshire may be 

 taken as an illustration of the life of the species in regions 

 where there is but one brood. The butterflies appear in 

 open woods and on cut-over lands in May and June. They 

 lay eggs upon the twigs of oak trees, one egg in a place and 

 generally near a leaf stem. The egg soon hatches into a 

 little caterpillar that crawls upon a near-by leaf and 

 begins the construction of its tubular nest by bending over 

 the margin and sewing it with golden silk. It utilizes this 

 nest chiefly as a tent for resting and sleeping and wanders 

 away from it generally to another leaf when it is ready to 

 feed. It grows very slowly, having before it all the weeks 

 of summer to complete its caterpillar growth. As it gets 

 larger it needs a new tent and is likely to desert its early 

 one. When it does this some observers have noted a 

 curious habit. It cuts loose all the silk that binds the 

 margin of the leaf down upon the blade so that the flap is 

 free to spring back to its original position. It would be 

 difficult to suggest an adequate explanation for this 

 habit. 



When autumn comes our caterpillar is faced with the 

 problem of passing through the winter successfully. It 

 must shelter itself from birds, spiders, predaceous beetles, 

 and many other enemies. It must find a means of keeping 

 out of the reach of snow and rain, for while it can survive a 

 great degree of cold as long as it keeps dry, it might easily 



