New Zealand and temperate North America may
seem opposed to this statement, but it really is not so. For in both these
cases the native vegetation has first been artificially removed by man and
the ground cultivated; and there is no reason to believe that any similar
effect would be produced by the scattering of any amount of foreign seed on
ground already completely clothed with an indigenous vegetation. We might
therefore conclude _a priori_, that the flora of such an island as St.
Helena would be of an excessively ancient type, preserving for us in a
slightly modified form examples of the vegetation of the globe at the time
when the island first rose above the ocean. Let us see then what botanists
tell us of its character and affinities.

The truly indigenous flowering plants are about fifty in number, besides
twenty-six ferns. Forty of the former and ten of the latter are absolutely
peculiar to the island, and, as Sir Joseph Hooker tells us, "with scarcely
an exception, cannot be regarded as very close specific allies of any other
plants at all. Seventeen of them belong to peculiar genera, and of the
others, all differ so markedly as species from their congeners, that not
one comes under the category of being an insular form of a continental
species." The affinities of this flora are, Sir Joseph Hooker thinks, {307}
mainly African and especially South African, as indicated by the presence
of the genera Phylica, Pelargonium, Mesembryanthemum, Oteospermum, and
Wahlenbergia, which are eminently characteristic of southern extra-tropical
Africa. The sixteen ferns which are not peculiar are common either to
Africa, India, or America, a wide range sufficiently explained by the
dust-like spores of ferns, capable of being carried to unknown distances by
the wind, and the great stability of their generic and specific forms, many
of those found in the Miocene deposits of Switzerland, being hardly
distinguishable from living species. This shows, that identity of _species_
of ferns between St. Helena and distant countries does not necessarily
imply a recent origin.

_The Relation of the St. Helena Compositae._--In an elaborate paper on the
Compositae,[71] Mr. Bentham gives us some valuable remarks on the
affinities of the seven endemic species belonging to the genera
Commidendron, Melanodendron, Petrobium, and Pisiadia, which forms so
important a portion of the existing flora of St. Helena. He says: "Although
nearer to Africa th