205 
Chap. XII.— B.S.] EXTINCTION OF OLDEST RACE. 
As soon as New Holland shall have been broken up 
into islands, as Unger predicts it will be, we may ex¬ 
pect its vegetation to assume the same aspect as that 
now presented by the Polynesian islands. The bulk 
of the plants, adapted as they are to the peculiar dry 
climate of the extratropical parts, would perish as 
soon as the climate became insular, and the Asiatic 
flora, which even now presses hard upon the northern 
parts of New Holland, would get the upper hand, as 
has been the case in the Pacific after the dissolution 
of its continent into those innumerable islands now 
called Polynesian. Plants with dry leathery leaves 
would be superseded by those having a more luxu¬ 
riant but weedy look; for that I take to be the prin¬ 
cipal physiognomic difference between the floras of 
extratropical Australia and tropical Asia. It must be 
evident that the inquiry Unger has set on foot about 
the former continental connection of Europe and 
Australia, as proved by fossils, cannot stop here. The 
abundance of the most typical forms of Australian 
mammals—the marsupials (opossum and kangaroo)—• 
in tertiary European deposits, will doubtless tempt 
some comprehensive mind to treat the subject from a 
zoological point of view. It is most important to as¬ 
certain whether the present fauna of Australia was al¬ 
ways associated with the present flora. I do not know 
of any reason why it should not; but a closer exami¬ 
nation of all the facts may possibly point to a different 
conclusion. It will probably turn out that in the 
Australian native population we behold the oldest as 
well as the lowest race of men—a race in many in- 
