OF OLD AND NEW WORLD 209 



entirely to the consideration of their allies to judge 

 in what part of the world they originated, and on 

 this basis there can be no question whatever that 

 cardui originated in America, and atalanta in the 



Old World. 



Two other species are in nearly the same cate- 

 gory as the last as regards their distribution on this 

 continent. These are the Spring Azure (Cyaniris 

 pseudargiolus) and the American Copper (Heodes 

 hypophlaeas), which many writers are inclined to 

 consider identical with argiolus and plilaeas of the 

 Old World. There can be no doubt of their exceed- 

 ingly close affinity, nor, on the other hand, of the 

 fact that whether species or variety, the forms ex- 

 isting in the New World can be separated from 

 those of the Old. With regard to Heodes, there 

 is but a single species of the genus, in its restricted 

 form, in either hemisphere. In each it extends 

 from ocean to ocean, although not found in the 

 high north, and inasmuch as the genera nearest to 

 it are also represented by species in each hemi- 

 sphere (more abundantly in the Old World than in 

 the New), it is difficult to form any proper judg- 

 ment concerning its place of origin, though it would 

 appear more probable on general grounds that it 

 originated in the Old World. The same general 



