In
his "Principles of Geology" (10th Edit. vol. ii p. 355) he adduces
evidence to show that pigs have swum many miles at sea, and are
able to swim with great ease and swiftness. I have myself seen a
wild pig swimming across the arm of the sea that separates
Singapore from the Peninsula of Malacca, and we thus have
explained the curious fact, that of all the large mammals of the
Indian region, pigs alone extend beyond the Moluccas and as far
as New Guinea, although it is somewhat curious that they have not
found their way to Australia.
The little shrew, Sorex myosurus, which is common in Sumatra,
Borneo, and Java, is also found in the larger islands of the
Moluccas, to which it may have been accidentally conveyed in
native praus.
This completes the list of the placental mammals which are so
characteristic of the Indian region; and we see that, with the
single exception of the pig, all may very probably have been
introduced by man, since all except the pig are of species
identical with those now abounding in the great Malay islands, or
in Celebes.
The four remaining mammals are Marsupials, an order of the class
Mammalia, which is very characteristic of the Australian fauna;
and these are probably true natives of the Moluccas, since they
are either of peculiar species, or if found elsewhere are natives
only of New Guinea or North Australia.
