﻿332 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loo 



be relative and in most cases intermediate between those of the gabbi 

 and brasiliensis groups. No attempt was made to compare tapitis 

 with South American cottontails or with the North American species 

 aquaticus, palustris, and insonus. 



Krumbiegel (1942) listed the named species of Central and South 

 American rabbits. His material consisted of seven specimens from 

 various sources representing three forms, and eight specimens col- 

 lected by Kj'ieg in the Chaco. The latter were referred to Sylvilagus 

 brasiliensis paraguensis Thomas. 



Hummelinck (1940) revised the cottontails of northern Venezuela, 

 northern Colombia, and adjacent islands. ^S*. nigronuchalis with 

 continentis, a subspecies, and S. cumanicus with subspecies super- 

 ciliaris, margaritae, and avius were recognized. Hummelinck's ac- 

 count includes all pertinent bibliographic references, all known local- 

 ity records, fuU descriptions, and detailed measurements of most of 

 the 39 specimens examined. Information is given on habits and 

 relative abimdance of the forms treated. 



CLASSIFICATION OF AMERICAN RABBITS 



The four genera of American rabbits recognized by Lyon (1904) are 

 Sylvilagus Gray, Limnolagus Mearns, Brachylagus Miller, and Romero- 

 lagus Merriam. Lyon divided Sylvilagus into subgenus Sylvilagus 

 (type, Lepus sylvaticus 'BQ,c]iDisxTi=S.floridanus mallurus Thomas) and 

 subgenus Microlagus Trouessart (type, Lepus cinerascens Allen). All 

 South American rabbits were assigned to typical Sylvilagus with Tapeti 

 Gray a synonym. The genus Limnolagus, according to Lyon, em- 

 braced aquaticus Bachman (type), palustris Bachman, and telmale- 

 monus Elliot. 



Nelson (1909) admitted three, instead of four, genera of American 

 rabbits. He recognized Sylvilagus, Brachylagus, and Romerolagus. 

 Microlagus was relegated to the synonymy of typical Sylvilagus, 

 while Tapeti Gray (Lepus brasiliensis Linnaeus, type) was revived as 

 a subgenus of Sylvilagus. Limnolagus was placed in the synonymy of 

 Tapeti. 



Material and information accumulated to date confii-m the in- 

 clusion of all South American rabbits within the genus Sylvilagus. 

 The South American cottontail (including nigronuchalis, cumanicus, 

 margaritae, superciliaris, and others) is specifically identical with the 

 North American Sylvilagus floridanus. The tapiti, S. brasiliensis 

 (including tapetillus, gabbi, andinus, and others), is distinguished from 

 all cottontails chiefly by smaller size, near obsolescence of tail, and by 

 the normal number of six mammae. These characters, together with 

 others of lesser importance, are barely sufficient to validate Tapeti 

 Gray as a subgenus of Sylvilagus. 



