24 AFRICAN GAME ANIMALS 



throw much Hght on the derivation of the continental Afri- 

 can fauna. The present fauna of the island gives conclu- 

 sive evidence of its separation from the African continent 

 before the influx of the present big-game fauna, probably- 

 some time before the Miocene. Just what its connection 

 was previous to this age is doubtful, but its fauna may, as 

 suggested by Sclater,* represent the ancient African fauna. 

 Since its separation several strays have reached it; in the 

 Pleistocene two species of pigmy hippopotamus and more 

 recently the bush pig. A fair per cent of its Chiroptera 

 have, without doubt, recently reached the island, so that 

 to-day its fauna is of a mixed character. This is equally 

 true of its earlier fauna. The lemuroids, which now char- 

 acterize it so remarkably, reached the island long after the 

 insectivores had attained their present specialization. 



Immediately after the close of the Cretaceous period in 

 Africa there existed a connection with Eurasia and Mada- 

 gascar which allowed an intermigration of the land fauna. 

 During most of the Eocene, Oligocene, and Miocene, Africa 

 was isolated from Eurasia but connected with Madagascar. 

 This long interval gave ample time for the development of 

 specialization in the mammals of Ethiopia. But we are 

 practically without any records of the mammals inhabit- 

 ing Africa at this period. The fragmentary evidence of the 

 Fayum beds is quite insufficient for the building of a picture 

 of the life of the vast continent of Africa which was then in 

 outline quite as at present. Much of Africa has been dry 

 land since the Permian age, and the great bulk of the in- 

 terior is to-day covered by Archaean rocks, which would indi- 

 cate a much greater antiquity. 



* Sclater, "Geog. Mams.," p. lo8. 



