The geographical distribution of animals, with a study of the relations ...

—426 ZOOLOGICAL GEOGRAPHY. [part hi.north coast of Australia then sank, cutting off the supply fromthat country ;and this left the Timorese group in the position itnow occupies.The reptiles and fishes of this group are too little known toenable us to make any useful comparison.Insects.—The insects, though not numerous, present many finespecies, some quite unlike any others in the Archipelago.arePapilio liris, Pieris lecta,Cirrochroa lamarckii and C. leschenaultiiamong butterflies.SuchThe Coleoptera are comparatively littleknown, but in the insects generally the Indo-Malay element predominates.This may have arisen from the peculiar vegetationand arid climate not being suitable to the Papuan insects.WhyAustralian forms did not establish themselves we cannot conjecture;but the field appears to have been open to immigrants fromJava, the climate and vegetation of which island at itseastern extremityapproximates to that of the Timorese group.The insectsare, however, so peculiarly modified as to imply a very great antiquity,and this is also indicated by a group of Sylviine birds hereclassedunder Oreicola, but some of which probably form disfinctgenera. There may, perhaps, have been an earlier and a laterapproximation to Java, which, with the other changes indicated,would account for most of the factspresented by the fauna ofthese islands. One deduction is, at all events, clear :the extremepaucity of indigenous mammals along with the absence ofso many groups of birds, renders it certain that the Timoreseislands did not derive their animal life by means of an actualunion with any of the large islands either of the Australian orthe Oriental regions.Celebes Group.—We now come to the Island of Celebes, inmany respects the most remarkable and interesting in the wholeregion, or perhaps on the globe, since no other island seems topresent so many curious problems for solution. We shall thereforegive a somewhat full account of its peculiar fauna, andendeavour to elucidate some of the causes to which its zoologicalisolation may be attributed.Mammalia.—The following is the list of the mammalia of