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Show 432 ISLAND LIFE. (!'ART H. both cases to the same conclusion, and forbids us to rank it as a stn.c tly contm. en t a1 I.S la nd on the Asiatic side. But f.a cts of. a very si·m i·1 ar cb aracter are equally opposed to the Idea of c • • a former land-connection with Australia or NeW: Gumea, or even with the Moluccas. The numerous marsupials of those coun t n·e s are a1 1 wanting in Celebes ' except the phalanger. s of the genus Cuscus, and these arboreal creatures are very hable t be carried across narrow seas on trees uprooted by earthq: akes or floods. The terrestrial cassowaries are equally absent; and thus we can account for the presence of all the Moluc~an or Australian types actually found in Celebes withou.t suppos.mg any land-connection on this side during the Tertiary per~od. rrhe presence of the Celebes ape in the i~land of B~tclnan, and of the babirusa in Bouru, can be suffiCiently explamed by a somewhat closer approximation of the respective lands, or by a few intervening islands which have since disappeared, or it may even be due to human agency. If the explanation now given of the peculiar features presented by the fauna of Celebes be the corr~ct on~: w~ are .fully justified in classinO' it as an "anomalous Island, smce It possesses a small but very remarkable mammalian fauna, without ever having been directly united with any conti~ent or extens~ve land; and, both by what it has and what It wants, occupies such an exactly intermediate position between the Oriental and Australian regions that it will perhaps ever remain a mere matter of opinion with which it should properly be associated. Forming, as it does, the western limit of such typical Australian groups as the Marsupials among mammalia, and the Trichoglossidre and Meliphagidre among birds, and being so strikingly deficient in all the more characteristic Oriental families and genera of both classes, I have alw:ays placed it in the Australian Region; but it may perhaps with equal propriety be left out of both till a further knowledge of its geology enables us to determine its early history with more precision. Peculiarities of the Insects of Oelebes.-The only other class of animals in Celebes, of which we have a tolerable knowledge, is that of insects, among which we meet with peculiarities of a very remarkable kind, ~nd such as are found in no other island CllAr. xx.] CELEBES. on the globe. Having already given a full account of some of these peculiarities in a paper read before the Linnean Society-republished in my OontribuNons to the Theory of Nat~cral Selection,-while others have been di~cussed in my Geographical Distribution of Animals (Vol. I. p. 434)-I will only here briefly refer to them in order to see whether they accord with, or receive any expbnation from, the somewhat novel view of the past history of the island here advanced. The general distribu1ion of the two best known groups of insects-the butterflies and the beetles-agrees very closely with that of the birds and mammalia, inasmuch as Celebes forms the eastern limit of a number of Asiatic and Malayan genera, and at the same time the western limit of several Moluccan and Australian genera, the former perhaps preponderating as in the higher animals. liimalayan Types of Bi?·ds and Butterflies in Oelebes.-A curious fact of distribution exhibited both amonO' butterflies b and birds, is the occurrence in Celebes of species and genera unknown to the adjacent islands, but only found again when we reach the Himalayan mountains or the Indian Peninsula. Among birds we have a small yellow flycatcher (Myialestes helianthea), a flower-peeker (Pachyglossa aureolimbata), a finch (Munia br~tnneiceps), and a roller ( Ooracias temminclcii), all closely allied to Indian (not Malayan) species,-all the genera, except Munia, ceing, in fact, unknown in any Malay island. Exactly parallel cases are two butterflies of the genera Dichorrhagia and Euripus, which have very close allies in the Himalayas, but nothing like them in any intervening country. These facts call to mind the similar case of Formosa, where some of its birds and mammals occurred again, under identical or closely allied forms, in the Himalayas; and in both instances they can only be explained by gojng back to a period when the distribution of these forms was very different from what it is now. Pec·uliarities of Shape and Oolou?· in Oelebesian Butterjlies.Even more remarkable are the peculiarities of shape and colour in a number of Celebesian butterflies of different genera. These are found to vary all in the same manner, indicating some general cause of variation able to act t1pon totally distinct F r |