124 



THE MAMMALIA. 



liar formation of the cheek-bone; however, as 

 regards the structure of its limbs it keeps wholly 

 within the limit of the Armadillo group. The 

 animal obtained its food by burrowing and scraping, 

 probably hid in caves, and protected itself from 

 the attacks of the not very powerful Carnivora, by 

 drawing its head under its breast like the arma- 

 dillo, its back being protected by a shield similar 

 to that of a gigantic 

 tortoise, its head by a 

 helmet of bony plates, 

 while the bony rings 

 of its tail were anchy- 

 losed, and formed a 

 kind of tunnel or 

 arched bridge of bone. 

 FIG. io.-Head of Glyptodon da- The Ant-bears of 



vipes. One-tenth natural size. 



After Burmeister. South America have 



an ancestor in the 



Ghssotherium. Another giant of Diluvial South 

 America but without any living representatives 

 is Toxodon, known to us by its skull, which 

 measures O60 metre; it possessed a more com- 

 plete dentition, but nevertheless shows affinity 

 to the Edentate type. Toxodon, owing to its 

 isolation, does not account for the existence of 



J 



