94 PROCEEDINGS OF THE AMERICAN ACADEMY 



plural form. The heading of the butterflies was Papilio, not Papilio- 

 nes ; of the swallow-tails, Equites, not Eques. 



That, if used at all, they should be retained in other than a generic 

 sense, is abundantly shown by tracing the mode in which these groups 

 of Linne, subordinate to the genus Papilio, became the divisions sub- 

 sequently termed families, and more comprehensive than the genera of 

 modern times. Even in the last century the term " families " was applied 

 to them; for when Cramer, in 1779, in the introduction to the first 

 volume of his great iconographic work, alluded to the classification of 

 Linne, it was introduced in these terms : " Je donnerai ici les divisions 

 de M. Linne, Papillons cinq families." Fabricius, when he first 

 attempted in 1807 to subdivide the butterflies into numerous genera, 

 retained the terms Papilio and Hesperia formerly used by him, greatly 

 restricting them of course ; but did not employ, in any form whatsoever, 

 the group-names previously in use, whether those given by Linne 

 or those established by himself, with a single exception, where he 

 divides Papilio into Trojaner and Achiver, just as the Equites (to which 

 he restricts Papilio) had before been divided into Trojarii and Achivi. 



But it is to French writers that we must look for the greatest light 

 upon this subject. In Cuvier's Tableau Elementaire (1798) we find 

 these groups of Linne, somewhat remodelled and placed under the two 

 genera then in use, Papilio and Hesperia : the groups, as here modified, 

 represent in the main the families of modern times. It was during the 

 activity of Latreille that the old genera began to be more and more 

 restricted and new genera to multiply, until, before his death and 

 through his writings, the interrelationship of genera and families 

 among butterflies was entirely reversed ; " families " having formerly 

 been considered divisions of "genera," while "genera" were now 

 looked upon as divisions of "families." In the first edition of Cuvier's 

 Regne Animal (1817), Latreille placed all the butterflies under one 

 "genus," Papilio, subdivided into groups termed " subgenera," which, 

 though differing greatly from the divisions of Linne, must really be 

 considered modifications of them, brought gradually about by the 

 progress of science ; a few, too, of Linne's names are retained. In 

 1825, in his Families Naturelles, the butterflies are divided into many 

 "genera," corresponding very closely to his previous subgeneric divi- 

 sions, and ranged under one "family," Diurna, exactly corresponding 

 to Linne's Papilio. In this connection, a study of the numerous 

 changes in classification introduced by Latreille in his different works 

 is very instructive. I have entered into the.se particulars, because 

 Messrs. Kirby and Crotch have recently endeavored to carry back 



