196 THE STORY OF BIRD-LIFE. 



reptiles of Africa, shows that this island must 

 have been separated from the continent very 

 early in the period known as the Tertiary, or 

 even earlier. This conclusion receives additional 

 testimony from the fact that Madagascar is stocked 

 with a very rich mammalian fauna, and one 

 which presents many remarkable peculiarities. 

 Many of them are of a very lowly and archaic 

 type. 



The richness of its mammalian fauna proves 

 its former connection with the mainland; whilst 

 the archaic character of this fauna shows that 

 the connection must have existed during a very 

 remote period when the fauna of that portion 

 of Africa at least, which was nearest the island, 

 was of a different and more primitive type than 

 the fauna now inhabiting this continent. Those 

 primitive forms have disappeared from the 

 mainland, and have given place to the more 

 specialised and vigorous types of to-day. No 

 other island possesses so many peculiar and 

 archaic mammalian forms; and no other island 

 on the globe, possessing a moderately rich 

 mammalian fauna, is separated from the main- 

 land by a sea whose depth exceeds one thousand 

 fathoms. What the great depth of this sea 

 teaches us will be shown presently. 



New Zealand carries the record of remote 

 isolation a step further. It possesses but two 

 known mammals, and these are bats ; and only 

 one frog-like animal. Its reptiles and birds 

 are very peculiar. 



Now the almost entire absence of endemic 

 mammals would point to an isolation from the 



