﻿330 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loo 



of tapitis from the continuously expanding artificial savannas and 

 scrublands of northwestern South America. Elsewhere tapitis live 

 successfully in at least superficially similar habitats. 



More precise geographic data regarding ranges of cottontails and 

 tapitis are given under the species and subspecies headings. 



LITERATURE 



Publications on indigenous leporids of South America include brief 

 descriptions of new forms, a few short reviews of what had been 

 regarded as species and species groups, and generalized comments on 

 the interrelationships of some forms. Broader works on leporids as a 

 whole and on lagomorphs in general have dealt sparingly and 

 cautiously with rabbits of South America. 



Lyon (1904) classified families and genera of lagomorphs chiefly on 

 the basis of osteological and dental characters. He included the 11 

 kinds of South American rabbits known at that time in the genus 

 Sylvilagus. He {op. cit., p. 334) regarded the generic name Tapeti 

 Gray as "nothing else than a part of Sylvilagus." 



Nelson (1909) discussed South American tapitis in connection with 

 his revision of North American leporids. He believed that Tapeti 

 Gray, with Limnolagus Mearns a synonym, was a valid subgenus of 

 Sylvilagus. Nelson then arranged the North American species of 

 Tapeti into two groups. One group included gabbi and palustris, the 

 other insonus and aquaticus. This heterogenous assemblage was based 

 on what Nelson {op. cit., p. 259) regarded as a "striking double 

 parallelism in the curious resemblance in both form and color between 

 the two representatives of this group in Mexico {S. g[abbi] truei and 

 iS'. insonus) and the two swamp rabbits of the United States {S. 

 palustris and S. aquaticus). S. g. truei of the humid tropical forests 

 of southern Mexico, in its rich dark colors, short ears, short slender 

 feet, and short tail is remarkably like S. palustris of the United States. 

 On the other hand, S. insonus of southwestern Mexico bears an equally 

 close superficial resemblance to ^S*. aquaticus of the United States. 

 ... It is difficult to decide whether these remarkable resemblances 

 point to a common origin, or merely represent parallel development." 

 The "superficial" external and cranial characters enumerated by 

 Nelson as indicative of close relationship between members of each 

 of the above groups are mainly family or individually variable char- 

 acters and do not support his classification. On the other hand, 

 Nelson failed to discuss the relationship of North and South American 

 cottontails. 



Thomas (1913) made the first attempt to clarify the interspecific 

 relationships of South American Leporidae. As a point of departure, 

 he restricted the type locality of Lepus brasiliensis Linnaeus to Per- 



