338 GEOGRAPHICAL AND GEOLOGICAL DISTEIBUTION. 



apar (Tolypeutes tricinctus), which, with the remaining members 

 of the generic group to which it belongs, has the power of rolling 

 itself into a complete ball ; and the great armadillo (Priodon gigas), 

 an inhabitant of the forests of Brazil and Guiana, the largest living 

 representative of the family, measuring upwards of three feet from 

 the tip of the nose to the root of the tail. 



Fossil remains of edentate animals are not numerous, and are in 

 the main confined to the Pliocene and Post-Pliocene deposits of the 

 New World, especially South America (Pampean formation of the 

 Argentine Republic ; bone-caves of Brazil). The oldest known form 

 is Ancylotherium priscum, from the phosphorites of Quercy, France 

 (Oligocene), a generalised type of animal, considered by some au- 

 thors to stand intermediate between the Edentata and Ungulata; the 

 same genus (A. Pentelici) occurs in the Miocene deposits of Pikermi, 

 Greece. An apparently allied form, Macrotherium, whose remains 

 indicate a possible climber of gigantic proportions, with compara- 

 tively feebly developed hinder extremities, is represented by several 

 species in the Miocene deposits of both France and Germany. No 

 New World forms are known to antedate the middle Tertiary period. 

 Moropus, from the Miocene and Pliocene deposits of the Western 

 United States, comprises animals ranging in size between the tapir 

 and rhinoceros, but with uncertain affinities; equally uncertain is 

 the position to be assigned to the Pliocene Morotherium, whose re- 

 mains have been found at various localities in Idaho and California. 



The South American edentate fauna (Pliocene and Post-Pliocene) 

 comprises, according to Gervais and Ameghino, some eighty or 

 more species, the greater number of which belong to genera now 

 no longer living. The better known forms are referable to the 

 families Megatheriidse and Glyptodontidse or Hoplophoridae, the 

 former of which appear to hold an intermediate position between 

 the modern sloths and ant-eaters — combining the head and denti- 

 tion of the one with the trunk and appendages of the other — while 

 the latter, in the presence of a carapace, approach the armadillos. 

 Included in the family Megatheriidse, besides other forms, are the 

 genera Megatherium, with animals of the size of the rhinoceros,* 



* Megatherium Amcrlcanum, from the Argentine Republic and Paraguay, 

 was only inferior in size to the elephant, far surpassing aU other land animals. 

 A mounted skeleton measures eighteen feet in length &om the fore part of the 

 head to the tip of the tail. 



