INTRODUCTION 
Although the island world which is ranged before 
the mainland of Africa in the Western part of the Indian. 
Ocean is far and away less imposing in extent than the 
Archipelago in the North East of this oceanic region, 
yet it is probably not in any way inferior in the individu¬ 
ality of its characteristics. 
Man and Nature here combine to form a world of 
itself, which, while markedly deviating from the con¬ 
tinental character, exhibits a singular mixture of the peculi¬ 
arities of African and Asiatic life, and this fundamental 
characteristic recalls, so to speak, the geological history 
of the East African islands. Certain points in the distri¬ 
bution of animals led long ago to the supposition oE 
an ancient connexion both with Southern Africa and 
Southern Asia, and in recent times our increased geological 
knowledge has made this supposition seem more and 
more probable. 
Of course the history of the formation of the several 
islands is neither uniform in character nor synchronous. 
Madagascar and the Seychelles appear to be the oldest 
members of the group; their insulation began in the 
mesozoic period and is connected with the formation of' 
the extensive sea-basin which is now filled by the,- 
