enable us to form a very good idea of the natural history of this group
of islands, and to derive therefrom some very interesting results.
The number of birds known from these islands up to this date is: 63 from
Lombock, 86 from Flores, and 118 from Timor; and from the whole group,
188 species. With the exception of two or three species which appear
to have been derived from the Moluccas, all these birds can be traced,
either directly or by close allies, to Java on the one side or to
Australia on the other; although no less than 82 of them are found
nowhere out of this small group of islands. There is not, however,
a single genus peculiar to the group, or even one which is largely
represented in it by peculiar species; and this is a fact which
indicates that the fauna is strictly derivative, and that its origin
does not go back beyond one of the most recent geological epochs. Of
course there are a large number of species (such as most of the waders,
many of the raptorial birds, some of the kingfishers, swallows, and a
few others), which range so widely over a large part of the Archipelago
that it is impossible to trace them as having come from any one part
rather than from another. There are fifty-seven such species in my list,
and besides these there are thirty-five more which, though peculiar to
the Timor group, are yet allied to wide-ranging forms. Deducting these
ninety-two species, we have nearly a hundred birds left whose relations
with those of other countries we will now consider.
If we first take those species which, as far as we yet know, are
absolutely confined to each island, we find, in:
Lombock 4 belonging to 2 genera, of which 1 is Australian, 1 Indian.
Flores 12 " 7 " 5 are " 2 "
Timor 42 " 20 " 16 are " 4 "
The actual number of peculiar species in each island I do not suppose
to be at all accurately determined, since the rapidly increasing numbers
evidently depend upon the more extensive collections made in Timor than
in Flores, and in Flores than in Lombock; but what we can depend more
upon, and what is of more special interest, is the greatly increased
proportion of Australian forms and decreased proportion of Indian forms,
as we go from west to east. We shall show this in a yet more striking
manner by counting the number of species identical with those of Java
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