Camarhynchus, is slightly parrot-shaped. Seeing this gradation and
diversity of structure in one small, intimately related group of birds,
one might really fancy that from an original paucity of birds in this
archipelago, one species had been taken and modified for different
ends. In a like manner it might be fancied that a bird originally a
buzzard, had been induced here to undertake the office of the
carrion-feeding Polybori of the American continent.
Of waders and water-birds I was able to get only eleven kinds, and of
these only three (including a rail confined to the damp summits of the
islands) are new species. Considering the wandering habits of the
gulls, I was surprised to find that the species inhabiting these
islands is peculiar, but allied to one from the southern parts of South
America. The far greater peculiarity of the land-birds, namely,
twenty-five out of twenty-six, being new species, or at least new
races, compared with the waders and web-footed birds, is in accordance
with the greater range which these latter orders have in all parts of
the world. We shall hereafter see this law of aquatic forms, whether
marine or fresh-water, being less peculiar at any given point of the
earth's surface than the terrestrial forms of the same classes,
strikingly illustrated in the shells, and in a lesser degree in the
insects of this archipelago.
Two of the waders are rather smaller than the same species brought from
other places: the swallow is also smaller, though it is doubtful
whether or not it is distinct from its analogue. The two owls, the two
tyrant-catchers (Pyrocephalus) and the dove, are also smaller than the
analogous but distinct species, to which they are most nearly related;
on the other hand, the gull is rather larger. The two owls, the
swallow, all three species of mocking-thrush, the dove in its separate
colours though not in its whole plumage, the Totanus, and the gull, are
likewise duskier coloured than their analogous species; and in the case
of the mocking-thrush and Totanus, than any other species of the two
genera. With the exception of a wren with a fine yellow breast, and of
a tyrant-flycatcher with a scarlet tuft and breast, none of the birds
are brilliantly coloured, as might have been expected in an equatorial
district. Hence it would appear probable, that the same causes which
here make the immigrants of some peculiar species smaller, make most of
the peculiar Galapageian species also smaller, as well as very
generally more dusky coloured. All the plants have a wretched, weedy
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