islands; and an herbaceous plant, which had no chance of successfully
competing with the many fully developed trees growing on a continent,
might, when established on an island, gain an advantage over other
herbaceous plants by growing taller and taller and overtopping them.
In this case, natural selection would tend to add to the stature of the
plant, to whatever order it belonged, and thus first convert it into a
bush and then into a tree.

ABSENCE OF BATRACHIANS AND TERRESTRIAL MAMMALS ON OCEANIC ISLANDS.

With respect to the absence of whole orders of animals on oceanic
islands, Bory St. Vincent long ago remarked that Batrachians (frogs,
toads, newts) are never found on any of the many islands with which the
great oceans are studded. I have taken pains to verify this assertion,
and have found it true, with the exception of New Zealand, New
Caledonia, the Andaman Islands, and perhaps the Solomon Islands and the
Seychelles. But I have already remarked that it is doubtful whether New
Zealand and New Caledonia ought to be classed as oceanic islands; and
this is still more doubtful with respect to the Andaman and Solomon
groups and the Seychelles. This general absence of frogs, toads and
newts on so many true oceanic islands cannot be accounted for by their
physical conditions; indeed it seems that islands are peculiarly fitted
for these animals; for frogs have been introduced into Madeira, the
Azores, and Mauritius, and have multiplied so as to become a nuisance.
But as these animals and their spawn are immediately killed (with the
exception, as far as known, of one Indian species) by sea-water, there
would be great difficulty in their transportal across the sea, and
therefore we can see why they do not exist on strictly oceanic islands.
But why, on the theory of creation, they should not have been created
there, it would be very difficult to explain.

Mammals offer another and similar case. I have carefully searched the
oldest voyages, and have not found a single instance, free from doubt,
of a terrestrial mammal (excluding domesticated animals kept by the
natives) inhabiting an island situated above 300 miles from a continent
or great continental island; and many islands situated at a much less
distance are equally barren. The Falkland Islands, which are inhabited
by a wolf-like fox, come nearest to an exception; but this group cannot
be considered as oceanic, as it lies on a bank in connection with the
mainland a