216 BUTTERFLIES 



and mammals we have geographical races distinctly rec- 

 ognized instead of separate species. 



While the study of butterflies has by no means received 

 the degree of attention which has been given the birds and 

 mammals, it is already evident that a similar condition pre- 

 vails with reference to many species. As the size of col- 

 lections has increased and more careful studies have been 

 made of the various forms from different regions it has been 

 found in numerous cases that they intergraded to so great 

 an extent that it is impossible to distinguish many species 

 which were formerly considered entirely distinct. One of 

 the most striking examples of this is found in the case of 

 our common Wood-nymph, which is sometimes called the 

 Blue-eyed Grayling. The form which is one of our most 

 abundant butterflies in southern New England and many 

 of the Eastern states was described as Satyrus alope by the 

 French naturalist Fabricius, who also described another 

 species from the Southern states as Satyrus pegala, and a 

 form found in northern Canada was described by the 

 English entomologist Kirby as Satyrus nejphele. Various 

 other forms from isolated regions have been given specific 

 names by other authorities. {See plates, pages 81, 208.) 



During recent years many collectors have gathered these 

 butterflies from all parts of North America and many 

 specimens have been grouped together in the more im- 

 portant collections. When this occurred it became easy 

 to see that this is essentially a variable species which 

 under varying climatic conditions has assumed slightly 

 different forms, so that we have a good illustration of 

 well-developed geographical races. The more important 

 of these are indicated in the synopsis of the Meadow- 

 browns on page 227. 



