508 



ISLAND LIFE. 



[PAET II. 



most recent origin and offering the simplest phenomena; and 

 begin with the British Isles as affording the best example of 

 very recent and well known Continental Islands. Reviewing 

 the interesting past history of Britain, we show why it is com- 

 paratively poor in species and why this poverty is still greater 

 in Ireland. By a careful examination of its fauna and flora it 

 is then shown that the British Isles are not so completely 

 identical, biologically, with the continent as has been supposed. 

 A considerable amount of speciality is shown to exist, and that 

 this speciality is real and not apparent is supported by the 

 fact, that small outlying islands, such as the Isle of Man, the 

 Shetland Isles, Lundy Island, and the Isle of Wight, all possess 

 certain species or varieties not found elsewhere. 



Borneo and Java are next taken, as illustrations of tropical 

 islands which may be not more ancient than Britain, but which, 

 owing to their much larger area, greater distance from the 

 continent, and the extreme richness of the equatorial fauna and 

 flora, possess a large proportion of peculiar species, though these 

 are in general very closely allied to those of the adjacent parts 

 of Asia. The preliminary studies we have made enable us to 

 afford a simpler and more definite interpretation of the peculiar 

 relations of Java to the continent and its differences from 

 Borneo and Sumatra, than was given in my former work {The 

 Geographical Distribution of Animals). ^ 



Japan and Formosa are next taken, as examples of islands 

 which are decidedly somewhat more ancient than those pre- 

 viously considered, and which present a number of very inter- 

 esting phenomena, especially in their relations to each other, 

 and to remote rather than to adjacent parts of the Asiatic 

 continent. 



We now pass to the group of Ancient Continental Islands, 

 of which Madagascar is the most typical example. It is sur- 

 rounded by a number of smaller islands which may be termed 

 its satellites since they partake of many of its peculiarities ; 

 though some of these — as the Comoros and Seychelles may be 

 considered continental, while others — as Bourbon, Mauritius, 

 and Rodriguez — are decidedly oceanic. In order to understand 

 the peculiarities of the Madagascar fauna we have to consider 



