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relations are unquestionable ; with them were also 

 found fragments of flowers which could have been 

 readily admitted as of the same species. It is 

 therefore highly probable that Prolibythea vaga- 

 bunda and Barbarothea florissanti fed on Celtis 

 maccoshi. 



The last American fossil is Stolopsyche, one of 

 the Pierini, more nearly allied to Pieris than to 

 any other, but not very closely allied ; wherein it 

 departs from it, it approaches some sub-tropical 

 forms. Little can be said of it, and nothing can 

 safely be surmised of its food plant. 



The aspect of the Florissant butterfly fauna is 

 therefore distinctly southern ; and while tertiary 

 America does not fully return the compliment ter- 

 tiary Europe seems to pay it, there is a certain 

 Old World aspect in the representatives of that 

 gypsy-type, the Libytheinae. 



There are one or two points further in our 

 American fossil butterflies which it is interesting 

 to note. In two or three of them the structure of 

 the front legs can be determined, and we are able 

 to note that in this oligocene time, among the ear- 

 liest butterflies that have come down to us, we 

 have the same structure of the fore leg in the 

 female Libytheinae that we have to-day ; while at 



