THE CLASSIFICATION OF THE AMERICAN SIPHON- 



APTERA. 



By Carl F. Bakek, 



Estacion Agronumica, Santiago de las Vegai^, Cuba. 



A previous paper, entitled A Revision of American Siphonaptera, 

 by the present author, which had ])een completed March 1, 1908, did 

 not finally appear until 1904." In the meantime, and immediately fol- 

 lowing the publication of this paper, there occurred a most extraordi- 

 nary activity among students of this group. In 1903 alone at least 

 seventeen papers relating to Siphonaptera were published. New and 

 extensive material was rapidly brought together from all parts of the 

 world, and a more comprehensive classification of the group was grad- 

 ually evolved. In the extensive paper by Tiralwschi,'' we have the 

 first conception of subfamilies. Several new genera have been added 

 by Wagner, Rothschild, Wahlgren, and Enderlein. 



All of this has profoundly affected the classification of American 

 fleas proposed in my Revision. The bringing up to date of that work 

 became increasingly urgent, since it was already being widely used by 

 American students, and quoted by those of other countries. 



The writer has had continuously under way extensive supplemen- 

 tary studies of the older species. In addition new material of a very 

 important nature has been accumulating. The following paper is a 

 preliminary study necessary before the new material could be worked 

 up. In the former paper attention was called for the first time 

 to the fact that, as a whole, rat fleas of the Tropics were far 

 more nearly related to the fleas of human beings than were those of 

 temperate regions. Tiraboschi, in his monographic study of the 

 relation of rats to the bubonic plague, does not emphasize this fact, 

 which appears to the writer to be the most important connected 

 with the whole matter. The outbreaks of plague in Mazatlan, and 

 now in Chile, remind us that it may soon come our turn, and that a 

 thorough understanding of the problems involved — as in the case of 

 mosquitoes and yellow fever — is a matter of inestimable importance. 



«Proc. U. S. Nat. Mus., XXVII, pp. 365-469, pis. x-xxvi. 

 ^Archiv. de Parasit., VIII, 1904. 



Proceedings U. S. National Museum, Vol. XXIX— No. 1417. 



121 



