144 SE4SONAL CHANGES AND HISTORIES. 



two or three successive broods in the course of 



the year. 

 At the very end of the season this butterfly will 



be found laying eggs, which hatch in a few days ; 



the little caterpillars, 

 after devouring their 

 egg-shells, refuse fur- 

 ther food and hiber- 

 nate ; these hibernat- 

 ing juvenile larvae be- 

 long to one of the 



FIG. 131. Brenthis Myrina, nat. size ; 



under surface on right (Harris). Placed tWO Sets OI individuals 

 here for comparison with B. Bellona. 



mentioned ; this we 



will term the aestival or summer series ; for by the 

 end of the following June the caterpillars have 

 attained their growth, and passing through the 

 chrysalis state, emerge as butterflies about the 

 middle of July ; these are the butterflies of mid- 

 summer, continuing upon the wing 

 until the end of September, in which 

 month they deposit their eggs ; these 

 eggs hatch in about a week, and the 

 little caterpillars hibernate as before. 

 The history of this aestival series is 

 quite similar to that of the larger Myrina, nat. size. 

 fritillaries, all of which are single-brooded, ap- 

 pear in early summer, lay their eggs early in the 

 autumn, and hibernate as juvenile larvae. 

 The second set of individuals, which we will 



FIG. 132. Chrys- 

 alis of Brenthis 



