136 CHARACTERS OF VERTEBRATE ANIMALS 



Order 12. — Edentates (Edentata) 



This very remarkable group includes a number of both Old 

 and New World forms, which are rather low in the scale, and 

 have had to adopt various expedients in order to avoid being 

 exterminated by the active competition of more highly organized 

 forms. It is very doubtful whether the Old World forms have 

 any special relation to the New World ones, or in other words 

 the order is a very artificial one. This comes out strikingly when 

 an attempt is made to discover common characters. About all 

 that can be said is, that the teeth are highly peculiar in character, 

 and that the digits are provided with curiously modified curved 

 hoofs. As to the former structures the term " edentate ", i.e. 

 toothless, is somewhat misleading, for though this is the case 

 with some forms, it is not generally true, though the front teeth 

 are always more or less deficient. A further point is that the 

 teeth are always devoid of enamel. 



Most of the Edentates are found only in South America, and 

 of these the following are representative species: — The Two-toed 

 Sloth {Cholcepus didactylus) (fig. 95) of Guiana and Surinam; the 

 Six-banded Armadillo [Dasypus sexcinctus) (fig. 96) of the South 

 American pampas; and the Ant- Bear {Myrmecophaga jubatd) of 

 Paraguay. Old World forms are: The Cape Ant-Eater or 

 Aard-Vark (Orycteropus Capensis) (fig. 97) of South Africa, and 

 the Long-tailed Pangolin {Manis pentadactyla) (fig. 98) of West 

 Africa. 



Order 13. — Pouched Mammals (Marsupialia) 



This is the only order in the Mammalian sub-class Meta- 

 THERiA, under which heading its leading characters have already 

 been given (p. 68). 



The great bulk of existing Marsupials are confined to Australia 

 and its adjacent islands, as far as Celebes, though the order is 

 also represented in America. The great interest attached to the 

 Australian forms is found in the way they have become specialized 

 in various directions to fill the most varying places in the economy 

 of nature. Other more highly organized mammals having been 

 absent, they have had the field to themselves without other serious 

 competition, and the places occupied in most parts of the world 



