426 ZOOLOGICAL GEOGRAPHY. [PART III. 
north coast of Australia then sank, cutting off the supply from 
that country ; and this left the Timorese group in the position it 
now occupies. 
The reptiles and fishes of this group are too little known to 
enable us to make any useful comparison. 
Insects.—The insects, though not numerous, present many fine 
species, some quite unlike any others in the Archipelago. Such 
are—Papilio liris, Pieris leta, Cirrochroa lamarckii and C. lesche- 
naultiti among butterflies. The Coleoptera are comparatively little 
known, but in the insects generally the Indo-Malay element pre- 
dominates. This may have arisen from the peculiar vegetation 
and arid climate not being suitable to the Papuan insects. Why 
Australian forms did not establish themselves we cannot conjec- 
ture; but the field appears to have been open to immigrants from 
Java, the climate and vegetation of which island at its eastern ex- 
tremity approximates to that of the Timorese group. The insects 
are, however, so peculiarly modified as to imply a very great anti- 
quity, and this is also indicated by a group of Sylviine birds here 
classed under Oreicola, but some of which probably form distinct 
genera. There may, perhaps, have been an earlier and a later 
approximation to Java, which, with the other changes indicated, 
would account for most of the facts presented by the fauna of 
these islands. One deduction is, at all events, clear: the ex- 
treme paucity of indigenous mammals along with the absence of 
so many groups of birds, renders it certain that the Timorese 
islands did not derive their animal life by means of an actual 
union with any of the large islands either of the Australian or 
the Oriental regions. 
Celebes Group—We now come to the Island of Celebes, in 
many respects the most remarkable and interesting in the whole 
region, or perhaps on the globe, since no other island seems to 
present so many curious problems for solution. We shall there- 
fore give a somewhat full account. of its peculiar fauna, and 
endeavour to elucidate some of the causes to which its zoological 
isolation may be attributed. 
Mammalia.—The following is the list of the mammalia of 
