o the productions of
islands. In the following remarks I shall not confine myself to the mere
question of dispersal, but shall consider some other cases bearing on
the truth of the two theories of independent creation and of descent
with modification.

The species of all kinds which inhabit oceanic islands are few in number
compared with those on equal continental areas: Alph. de Candolle admits
this for plants, and Wollaston for insects. New Zealand, for instance,
with its lofty mountains and diversified stations, extending over 780
miles of latitude, together with the outlying islands of Auckland,
Campbell and Chatham, contain altogether only 960 kinds of flowering
plants; if we compare this moderate number with the species which swarm
over equal areas in Southwestern Australia or at the Cape of Good Hope,
we must admit that some cause, independently of different physical
conditions, has given rise to so great a difference in number. Even the
uniform county of Cambridge has 847 plants, and the little island of
Anglesea 764, but a few ferns and a few introduced plants are included
in these numbers, and the comparison in some other respects is not quite
fair. We have evidence that the barren island of Ascension aboriginally
possessed less than half-a-dozen flowering plants; yet many species have
now become naturalised on it, as they have in New Zealand and on every
other oceanic island which can be named. In St. Helena there is reason
to believe that the naturalised plants and animals have nearly or quite
exterminated many native productions. He who admits the doctrine of the
creation of each separate species, will have to admit that a sufficient
number of the best adapted plants and animals were not created for
oceanic islands; for man has unintentionally stocked them far more fully
and perfectly than did nature.

Although in oceanic islands the species are few in number, the
proportion of endemic kinds (i.e. those found nowhere else in the world)
is often extremely large. If we compare, for instance, the number of
endemic land-shells in Madeira, or of endemic birds in the Galapagos
Archipelago, with the number found on any continent, and then compare
the area of the island with that of the continent, we shall see that
this is true. This fact might have been theoretically expected, for, as
already explained, species occasionally arriving, after long intervals
of time in the new and isolated district, and having to com