1 84 



ARMOURED EDENTATES 



The iVIegatheriidae 



This 

 liad, 



Zamicrus had a skull no bigger than that of a 



On the manus, the three inner digits have powerful claws, 

 animal, too, was Pleistocene in time, 

 however, small as well as gigantic forms. 



The genus 



Sloth, while Nothrotlieriicm was also a comparatively small 

 creature ; the teeth of the latter genus are reduced to -^. 



The extinct group of the Glyptodontidae comprises large 

 creatures with a dense covering of bony scutes which are arranged 

 in a tesselated fashion, and thus form an immobile armature of 

 immense strength. In correspondence with this massive carapace 

 the dorsal vertebrae have fused together, and the lumbar vertebrae 

 form a series ankylosed to each other and to the following sacrals. 

 These creatures are all South American. 



Ghjptodon, the genus which gives its name to the family, is 

 known from numerous remains in South America, and also from 



Fig. 106. — Ulyptodmi dacipes. x jV. (After Owen.) 



so far north as Texas and Mexico. It grew to be as Ions as 16 

 or 17 feet. In the skull there is an exceedingly long 

 downward process (jf the zygomatic arch, as in Sloths, the arch 

 itself lieing complete. The process extends so far down as to- 

 reach a point about on a level with the middle of the lower jaw. 

 The nasals are short or rudimentary. As in Mij'nnccopliagu, the 

 pterygoids enter into the formation of the bony palate. The 

 lower jaw has a spout-shaped extremity, and, behind, it rises into 

 an enormous vertical branch as high as the front part of the jaw 

 is long. There are eight teeth in each half of each jaw. As in 



