218 LAND MAMMALS IN THE WESTERN HEMISPHERE 



found in the Brazilian caverns, but this is no doubt due to the 

 accidents of preservation, for the latter animal ranged north 

 to Nicaragua. 



The rodents likewise were partially of immigrant and par- 

 tially of native stock. To the former belonged the few mice 

 and rats and a meadow-mouse {Microtus), a group not repre- 

 sented in present-day South America, and a rabbit. Very 

 much more abundant and varied were the indigenous forms, all 

 of which belonged to existing families and most of them to exist- 

 ing genera ; the tree-porcupines, cavies, agoutis, spiny-rats, viz- 

 cachas, capybaras, coypus, etc., were abundantly represented, 

 for the most part by extinct species. 



The monkeys were of purely Neotropical type and several 

 modern genera, such as Cebus and Callithrix, and one very 

 large extinct genus, fProtopithecus, of the same family, have 

 been found in the caverns of Brazil, but not in the pampas of 

 Argentina, which would seem to have been a country of open 

 plains. 



In the South America of to-day one of the most striking 

 and peculiar elements of the fauna is that formed by the Eden- 

 tata, the sloths, anteaters and armadillos, and this was even 

 more true of the same region in Pleistocene times. Anteaters 

 and sloths are very scantily represented, but this is merely 

 an accident of preservation ; armadillos, on the other hand, 

 were very numerous both in Brazil and in Argentina, and, in 

 addition to many modern genera, there were several which 

 are no longer in existence, such as "^Chlamydotheriwm, which 

 was a huge creature almost as large as a rhinoceros. Then 

 there were the two extinct suborders of the fglyptodonts 

 (fGlyptodontia) and the fground-sloths (fGravigrada) which 

 were astonishingly abundant in Argentina and which, as was 

 shown in a previous page (p. 205), were also well represented in 

 North America. 



Few more fantastic-looking mammals than the fglyptodonts 

 have ever been found; the short, deep head, with its shield 



