vi] DISTRIBUTION OF SELECTED GROUPS 141 



with the close of the Miocene permanent connexion 

 with North America was reestablished. This brought 

 the modern odd-toed and pair-toed Ungulates, with 

 dogs, cats and bears in their wake, and lastly man. 



There remains the huge North World. Eurasia 

 and North America have always formed a wide 

 circumpolar ring, which repeatedly broke and joined 

 again. Whatever group of terrestrial creatures was 

 developed in the eastern, Asiatic, half, was sure to 

 turn up in the western, and vice versa. 



Lastly, the mysterious African continent. It began 

 originally as the centre of the ancient equatorial South 

 World ; it has lost these connexions and has become 

 joined to the northland, after many vicissitudes. It 

 is therefore most difficult to apportion its fauna 

 rightly ; moreover for fossils it is almost a blank, 

 except Egypt. It must have had some share in the 

 evolution of mammals, like edentates, rodents, In- 

 sectivores, hyrax, elephants, sirenians and lemurs, 

 all groups with an ancient stamp. But what share 

 it had, against Eurasia, in the development of say 

 Ungulates, Carnivores, monkeys, we do not know. 

 Not much is likely to have originated in Europe ; the 

 elephants, rhinos, hippos, lions and hyaenas were 

 migrants rather from than to Africa, rarely across 

 some Mediterranean bridge, usually by Asia Minor. 



The more dominant forms of our present fauna 

 have originated, to use an expression of Darwin's, 



