nts? and why should the Cape of Good Hope, characterised
by the uniformity of its scenery, swarm with more species of plants than
probably any other quarter of the world? Why on the ordinary theory
should the Galapagos Islands abound with terrestrial reptiles? and why
should many equal-sized islands in the Pacific be without a single
one{386} or with only one or two species? Why should the great island of
New Zealand be without one mammiferous quadruped except the mouse, and
that was probably introduced with the aborigines? Why should not one
island (it can be shown, I think, that the mammifers of Mauritius and St
Iago have all been introduced) in the open ocean possess a mammiferous
quadruped? Let it not be said that quadrupeds cannot live in islands,
for we know that cattle, horses and pigs during a long period have run
wild in the West Indian and Falkland Islands; pigs at St Helena; goats
at Tahiti; asses in the Canary Islands; dogs in Cuba; cats at Ascension;
rabbits at Madeira and the Falklands; monkeys at St Iago and the
Mauritius; even elephants during a long time in one of the very small
Sooloo Islands; and European mice on very many of the smallest islands
far from the habitations of man{387}. Nor let it be assumed that
quadrupeds are more slowly created and hence that the oceanic islands,
which generally are of volcanic formation, are of too recent origin to
possess them; for we know (Lyell) that new forms of quadrupeds succeed
each other quicker than Mollusca or Reptilia. Nor let it be assumed
(though such an assumption would be no explanation) that quadrupeds
cannot be created on small islands; for islands not lying in mid-ocean
do possess their peculiar quadrupeds; thus many of the smaller islands
of the East Indian Archipelago possess quadrupeds; as does Fernando Po
on the West Coast of Africa; as the Falkland Islands possess a peculiar
wolf-like fox{388}; so do the Galapagos Islands a peculiar mouse of the
S. American type. These two last are the most remarkable cases with
which I am acquainted; inasmuch as the islands lie further from other
land. It is possible that the Galapagos mouse may have been introduced
in some ship from the S. American coast (though the species is at
present unknown there), for the aboriginal species soon haunts the goods
of man, as I noticed in the roof of a newly erected shed in a desert
country south of the Plata. The Falkland Islands, though between 200 and
300 miles from the S