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Section VII.—The Papuan Sub-region
In contrast to Australia, the great island of New Guinea, or Papua, is traversed throughout by mountains of high altitude. The rivers rising in these ranges, aided by the suns of the tropics, produce a luxuriant vegetation, and such a country as we should suppose would be especially favourable to mammal-life. Yet mammals are by no means abundant in New Guinea and in the adjacent islands which constitute the Papuan Sub-region. As is the case in Australia, the greater number of the indigenous animals of New Guinea and the neighbouring islands consist of Monotremes, Marsupials, and Rodents, together with a certain number of the cosmopolitan order of Bats (8, 10,11).
Of the Monotremes, two species have been met with in New Guinea, both of them belonging to the family of Echidnas above referred to. Of these one species, only at present known from the south of New Guinea, is but a slightly modified form of the small Australian Echidna. But in the mountains, in various parts of New Guinea, has been lately discovered a larger representative of the same family (Proechidna), which, moreover, differs from the typical form in having only three toes on its fore limbs, and in other particulars (Fig. 6, p. 38).
The Papuan Marsupials, as yet discovered, are about thirty-three in number, and embrace representatives of the Dasyures, Bandicoots, Phalangers, and Kangaroos, which are also characteristic families of the Australian mammalfauna.
There are only two genera of Marsupials peculiar to the Papuan Sub-region. One of these is Distcechurus, a small mouse-like animal belonging to the family of Phalangers, and remarkable for its long tail, which bears at its tip a double row of hairs on either side, and thus resembles a feather. The other genus is Dorcopsis, containing three species of animals somewhat nearly allied to the true
Fig. 6.—The Papuan Echidna.
Kangaroos. A third genus (Dendrolagus), containing Kangaroos specially modified for arboreal life, was formerly supposed to be peculiar to New Guinea. But a species of the same form, as already mentioned, has been ascertained of late years to exist in Northern Queensland also, thus giving further proof of the close alliance of the Papuan and Austral mammal-faunas.
Nearly all the Marsupials found in the Papuan Subregion are confined to the island of New Guinea; a few, however—for example, the Phalangers—also inhabit the other islands of this Sub-region. The Grey Cuscus (Phalanger orientalis) extends from Amboyna in the Moluccas and from Timor all across New Guinea, and as far east as New Britain and the island of San Christoval in the Solomons. As regards the remaining orders of mammals, a few scattered representatives of the higher forms (Ungulates, Insectivores, and Carnivores) are found in the islands of the Papuan Sub-region. Some of these have, undoubtedly, been introduced by the Malays from the neighbouring islands of the Oriental Region; but others have been described by naturalists as peculiar species. In the latter case, even if we assume that the specific distinctions have been satisfactorily established, it is not probable that such species have been brought into the Papuan Region by the hand of man. It is more likely that they have migrated into it at an earlier period, since a considerable lapse of time is necessary before the effects of isolation can produce new races of sufficient distinctness from the original form to be entitled to specific separation. As regards the Papuan Ungulates, several kinds of Swine (Sus) are stated to be met with in the Papuan Region. How far these differ from one another, and whether they are really distinct from the allied wild pigs of the Oriental Region, seems a little uncertain. It is probable, however, that many of these so-called " species" of wild pig may be descendants of the domestic animal, which has run wild, as is well known, in many of the Pacific Islands. The other representatives of the Order Ungulata found in the Papuan Sub-region are three species of Deer belonging to what is termed the Rusine group of the genus Cervus. Two of these deer are confined to Timor and the Moluccan group of islands respectively. All three are closely allied to the Javan Deer (Cervus hippelaphus), and it is quite possible that they are merely dwarfed forms of this species.
Passing over, for the present, the Rodents and Bats, the Carnivora are represented in the Papuan Region by three species. These are a Cat (Felis megalotis), of which very little is known, but which is stated on competent authority to be quite a distinct species, and to be confined to the islands of Timor and Rotti; a Palm-cat (Paradoxurus hermaphroditus), and a Civet (Viverra tangalunga). Of these two the Palm-cat is found in both the Moluccas and the Timor group, the Civet only in the Moluccas. These animals have in all probability been introduced by the Malays, since they are both frequently kept by them as pets in captivity.
The Order Insectivora is represented in the Papuan Sub-region by about five species of small Shrews (Crocidura), but, so far as is yet known, these occur only in the Moluccas and in Timor, and do not reach further east. Lastly, two species of Monkeys just enter the margin of the Sub-region, namely, the Common Macaque (Macacus cynomolgus), very widely distributed throughout the Oriental Region, which has crossed "Wallace's Line" into Flores and Timor; and the Black Ape of Celebes (Cynopithecus niger), which has passed the narrow straits between that island and Batchian, one of the Molucca group.
The Rodents are represented in the Papuan Sub-region by a considerable number of rats and mice of the family Muridm, all of them restricted to the Sub-region. One of these, remarkable for its peculiar and probably prehensile tail, is found only in the mountains of New Guinea, and has been placed in a new genus (Chiuromys). Among the Rodents also there is one very obvious intruder from the west; this is the Javan porcupine (Hystrix javanica), which in this Sub-region is found only in Timor, but is very widely distributed throughout the Oriental Malayan Islands.
Finally, the Papuan Sub-region, with its luxuriant vegetation and tropical forests, seems to be extremely favourable to the presence of Bats, of which there are more than sixty species known to occur within its limits. More especially is this the case with the large fruit-eating bats of the genus Pteropus, since about twenty out of the forty known species of this genus are found within this Subregion. This genus (Pteropus) has a remarkable area of distribution, which it is difficult to account for satisfactorily. Its range extends from Madagascar and the neighbouring Mascarene Islands through the Seychelles to India, Ceylon, Burma, and the Malayan Archipelago, and includes even Southern Japan; thence it is continued over all the Papuan Sub-region into Australia and most of the Polynesian Islands. This genus, it may be noted, seems to have a special propensity to peculiar development in insular areas. Out of about forty species of Pteropus as yet known, only two (Pteropus medius from India, and Pteropus edulis of the Malay Peninsula) are found on the main continental mass; all the other species are confined to islands, and in many cases to very small limits. For instance, one species (P. livingstonii) is restricted to the Comoro Islands in the Indian Ocean, three others to single