SOUTH-AMERICAN MAMMALS. 425 



genera have yet been discovered in Europe, Asia, or Africa. 

 The types of Bradypus and Dasypus were, however, richly 

 represented by diversified and gigantic specific forms in South 

 America during the geological periods immediately preceding 

 the present. The skeleton of one of these forms of the sloth 

 tribe is represented in fig. 166; it measures, from the fore 



Fig. 166. 

 Extinct Terrestrial Sloth, Mylodon robustus (Pleistocene, S. America). 



part of the skull to the end of the tail, 11 feet. It was dis- 

 covered buried 12 feet deep in the nuviatile deposits seven 

 leagues north of the city of Buenos Ayres in the year 1841. 

 It forms the subject of a work entitled, Description of the 

 Skeleton of an Extinct Gigantic Sloth (Mylodon robustus)* in 

 which are set forth in detail the grounds for regarding it as a 

 member of the same natural family as the present small arbo- 

 real sloth, and as being modified to obtain its leafy food by 

 uprooting and prostrating trees. 



A still larger species of terrestrial sloth (Megatherium, 

 Cuv.) co-existed with the Mylodon in South America. Its 



* 4to, 1842, Van Voorst. 



