to occur on several of the small low islands in the Pacific. At
Ascension, where there is no land-bird, a rail (Porphyrio simplex) was
shot near the summit of the mountain, and it was evidently a solitary
straggler. At Tristan d'Acunha, where, according to Carmichael, there
are only two land-birds, there is a coot. From these facts I believe
that the waders, after the innumerable web-footed species, are
generally the first colonists of small isolated islands. I may add,
that whenever I noticed birds, not of oceanic species, very far out at
sea, they always belonged to this order; and hence they would naturally
become the earliest colonists of any remote point of land.
Of reptiles I saw only one small lizard. Of insects I took pains to
collect every kind. Exclusive of spiders, which were numerous, there
were thirteen species. [4] Of these, one only was a beetle. A small
ant swarmed by thousands under the loose dry blocks of coral, and was
the only true insect which was abundant. Although the productions of
the land are thus scanty, if we look to the waters of the surrounding
sea, the number of organic beings is indeed infinite. Chamisso has
described [5] the natural history of a lagoon-island in the Radack
Archipelago; and it is remarkable how closely its inhabitants, in
number and kind, resemble those of Keeling Island. There is one lizard
and two waders, namely, a snipe and curlew. Of plants there are
nineteen species, including a fern; and some of these are the same with
those growing here, though on a spot so immensely remote, and in a
different ocean.
The long strips of land, forming the linear islets, have been raised
only to that height to which the surf can throw fragments of coral, and
the wind heap up calcareous sand. The solid flat of coral rock on the
outside, by its breadth, breaks the first violence of the waves, which
otherwise, in a day, would sweep away these islets and all their
productions. The ocean and the land seem here struggling for mastery:
although terra firma has obtained a footing, the denizens of the water
think their claim at least equally good. In every part one meets
hermit crabs of more than one species, [6] carrying on their backs the
shells which they have stolen from the neighbouring beach. Overhead,
numerous gannets, frigate-birds, and terns, rest on the trees; and the
wood, from the many nests and from the smell of the atmosphere, might
be called a sea-rookery. The gannets, sitting on their rude nests,
gaze at one with a stupid yet angry air. The noddies, as their name
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