428 ZOOLOGICAL GEOGRAPHY. [PART IIL, 
Australian form is represented in Celebes by two peculiar 
species. 
Leaving out the Indo-Malay species, which may probably have 
been introduced by man, and are at all events comparatively 
recent immigrants, and the wild pig, a genus which ranges over 
the whole archipelago and which has therefore little significance, 
we find two genera which have come from the Australian side, 
—Cuscus and Mus ; and four from the Oriental side,—Cynopi- 
thecus, Anoa, Babirusa, and Sciurus. But Sciurus alone corre- 
sponds to Cuscus,as a genus still inhabiting the adjacent islands; 
the other three being not only peculiar to Celebes, but incapable 
of being affiliated to any specially Oriental group. We seem, then, 
to have indications of two distinct periods; one very ancient, 
when the ancestors of the three peculiar genera roamed over some 
unknown continent of which Celebes formed, perhaps, an outlying 
portion ;—another more recent, when from one side there entered 
Sciurus, and from the other Cuscws. But we must remember 
that the Moluccas to the east, possess scarcely any indigenous 
mammals except Cuscus; whereas Borneo and Java on the west, 
have nearly 50 distinct genera. It is evident then, that the 
facilities for immigration must have been much less with the 
Oriental than with the Australian region, and we may be pretty 
certain that at this later period there was no land connection 
with the Indo-Malay islands, or some other animals than squirrels 
would certainly have entered. Let us now see what light is 
thrown upon the subject by the birds. 
Birds—The total number of birds known to inhabit Celebes 
is 205, belonging to about 150 genera. We may leave out of 
consideration the wading and aquatic birds, most of which are 
wide-ranging species. There remain 123 genera and 152 species 
of land-birds, of which 9 genera and 66 species are absolutely 
confined to the island, while 20 more are found also in the Sula 
or Sanguir Islands, so that we may take 86 to be the number of 
peculiar Celebes species. Lord Walden, from whose excellent 
paper on the birds of Celebes (Zrans. Zool. Soc. vol. viii. p. 23) 
most of these figures are obtained, estimates, that of the species 
which are not peculiar to Celebes, 55 are of Oriental and 22 of 
