DERIVATION OF THE FAUNA 23 



giraffe, the hyena, the civet, and the mongoose. Nearly 

 all of these forms continued to exist in southern Europe and 

 Asia until the close of the Pliocene. The commonly ac- 

 cepted theory, however, derives the present African fauna 

 from southern Europe and Asia. The facts which we have 

 at present certainly support this theory, but the case is 

 not well balanced, Eurasia with its extensive Miocene beds 

 being weighed against the Miocene void in Africa. What 

 mammals inhabited Ethiopian Africa during middle or 

 early Tertiary times we do not know, as no fossil-bearing 

 beds of these ages have been discovered. It is certain, 

 however, that Africa is one of the oldest continents and may 

 well have been the birthplace of some groups of mammals. 

 Osborn,* from the evidence found in the Fayum beds, con- 

 siders it probable that Africa was the original home of the 

 elephants, sirenians, toothed whales, and hyraxes. Not- 

 withstanding the presence in the Mediterranean region of 

 Africa of early Tertiary generalized types of Proboscidean 

 HyracoideUy and ungulates, it is doubtful whether such forms 

 gave rise in any important degree to the present African 

 fauna. These Miocene forms exhibit such primitive char- 

 acters that their relationships with the modern fauna can- 

 not be well estabhshed. Owing to the incompleteness of 

 the fossil records, the direct ancestral forms of the living 

 antelopes are still unknown. The Miocene antelopes of 

 Europe and Asia were as specialized as the existing species, 

 while, in the older beds of Oligocene and Eocene age, allied 

 types are quite wanting. 



The large island of Madagascar, which to-day has a very 

 peculiar fauna of lemurs, insectivores, and rodents, does not 



* Osborn, "Age of Mammals," 1910, p. 73. 



