In 1845, and subsequently in a pamphlet "On
the Physical Geography of South-Eastern Asia and Australia",
dated 1855, that a shallow sea connected the great islands of
Sumatra, Java, and Borneo with the Asiatic continent, with which
their natural productions generally agreed; while a similar
shallow sea connected New Guinea and some of the adjacent islands
to Australia, all being characterised by the presence of
marsupials.
We have here a clue to the most radical contrast in the
Archipelago, and by following it out in detail I have arrived at
the conclusion that we can draw a line among the islands, which
shall so divide them that one-half shall truly belong to Asia,
while the other shall no less certainly be allied to Australia. I
term these respectively the Indo-Malayan and the Austro-Malayan
divisions of the Archipelago.
On referring to pages 12, 13, and 36 of Mr. Earl's pamphlet, it
will be seen that he maintains the former connection of Asia and
Australia as an important part of his view; whereas, I dwell
mainly on their long continued separation. Notwithstanding this
and other important differences between us, to him undoubtedly
belongs the merit of first indicating the division of the
Archipelago into an Australian and an Asiatic region, which it
has been my good fortune to establish by more detailed
observations.
Contrasts in Natural Productions.
