THE CLOUDED YELLOW BUTTEIIFLY. 115 



From the eggs of Editsa both yellow and white 

 specimens have been reared ; this of course would be 

 a satisfactory proof of their not being distinct species. 

 With regard to the variation in markings, it has been 

 noticed that we had several illustrations last year of 

 specimens closely resembling continental ones bear- 

 ing a different specific name. When the full history 

 of the genus comes to be written, it will doubtless be 

 a deeply interesting one ; and will tend to show the 

 great probability that many so called species are but 

 variations of one original form, such variations being 

 attributable to differences in food, climate, and other 

 physical surroundings. 



