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of itself, is practically confined to the Region, although it has slightly overstepped its boundaries, being said to occur in one of the smaller Austro-Malayan islands between Sumba and Timor. Besides the Lemurs, six genera of true Monkeys are found in the Oriental Region. Three of these, the Proboscis Monkey of Borneo (Nasalis), the Gibbons (Hylobates), and the Orangs of Sumatra and Borneo (Simia), are strictly endemic; while the other three, although highly characteristic of this Region, have extended their range slightly across its frontiers.
Summarizing these results, we shall find that the Oriental Region contains only two truly endemic and one quasi-endemic families out of a total of thirty-six which occur within its limits. These are the Qaleopithecidse (Flying Lemurs), Tupaiidm (Tree shrews), and Tarsiidm (Tarsiers).
The total number of genera found in the Region is 113, out of which 38 are peculiar; 11 extend their ranges slightly beyond the limits of the Region, and 64 are widely spread. On reducing these figures to an average, it will be found that the Oriental Region contains about 38 per cent. of peculiar genera, or, if the quasi-endemic genera be added, about 45 per cent. In either case, this shows a much lower percentage of peculiarities than has been shown to exist in the three Regions previously considered.
Section III.—Subdivision Of The Oriental Region
The Oriental Region, as regards its mammals, may be most conveniently divided into four Sub-regions (see Map, Plate V., p. 152). These are :—
1. The Indian Sub-region.—This comprises the whole of India proper from the Suliman range and the lower slopes of the Himalayas to Cape Comorin. A line drawn northwards from Calcutta to the Himalayas, forms the approximate eastern boundary between this Sub-region and the next. There should also be included in this Sub-region the island of Ceylon, and probably the narrow, low-lying strip of desert country between the Persian Gulf and the central plateau of Persia.
2. The Burmo-Chinesc Sub-region.—This Sub-region includes the portion of Sikkim below 10,000 feet, Assam, China south of the northern water-parting of the Yang-tzeKiang, the islands of Formosa and Hainan, and all the countries of the Indo-Chinese peninsula (Cochin China, Siam, and Burma), its southern land-boundary being approximately a line running to the north of the Malay peninsula from Tavoy on the west, to Bangkok on the east, at about 15° N. lat.
3. The Malayan Sub-region.—The Malay peninsula, together with the great islands of the East Indian archipelago, Sumatra, Java, Borneo, and the Philippines, forms a third division, which may be called the Malayan Sub-region.
4. The Celebesian Sub-region, containing only the island of Celebes.
This subdivision of the Oriental Region differs from that adopted by Wallace in two important points:—
(a) In the combination of Wallace's Indian and Ceylonese Sub-regions into one—the Indian Sub-region.
(b) In the transference of Celebes from the Australian to the Oriental Region, and the formation of a new Subregion for its reception.
The reasons for these changes may be here briefly considered. First, as regards Ceylon, there are nineteen genera of mammals found in the Indian Sub-region, which do not extend their range further eastwards into the BurmoChinese Sub-region. Of these, thirteen are to be met with also in the Palsearctic and Ethiopian Regions, leaving only six confined to the Indian Sub-region. These six are—
(1) Tetraceros (Four-horned Antelope).
(2) Antilope (Black Buck).
(3) Boselaphus (Nylghaie).
(4) Platacanthomys (Spiny Rat).
(5) Melursus (Indian Bear).
(6) Loris (Slender Lemur).
Of these, Loris alone is characteristic of Southern India and Ceylon (the Ceylonese Sub-region of Wallace). Afelursus is found in Ceylon, but occurs also all over the peninsula of India from the Himalayas southwards. Platacanthomys inhabits the western Ghats and the Animali hills of Southern India alone, and not Ceylon; the remaining three genera are distributed over the whole of the Indian peninsula, but do not reach Ceylon.
There is, therefore, only one genus of mammals confined to the Ceylonese Sub-region of Wallace, and this hardly seems to afford an adequate reason for separating it from the Indian Sub-region proper. The chief ground for so doing, according to Mr. Wallace, is the existence there of a peculiar family of snakes—the Uropeltidm, or Rough-tails, which are entirely confined to Wallace's Ceylonese Sub-region. Examples of these reptiles, however, have been recorded in India as far north as Ganjam, in 20° N. lat., and it seems probable that they may eventually be found all over the peninsula south of the great plains of the Indus and the Ganges.
Secondly, as regards Celebes, this island certainly presents a difficult problem to the student of geographical distribution. But so far as the mammals are concerned, the only Australian element in Celebes consists of two species of Phalanger and a few Bats; the remaining forms, although many of them are very peculiar, have been, doubtless, originally derived from the Oriental rather than from the Australian Region. It seems more logical, therefore, on the whole, to make the island of Celebes a separate Sub-region of the Oriental rather than of the Australian Region. This position, however, will be considered in greater detail in the account of the Sub-regions.
Section IV.—The Indian Sub-region
The Indian Sub-region has a close resemblance to the Palaearctic Region. This is more especially the case in the north-western districts, where the country is practically rainless, and the fauna, owing to similarity of condition, is in many respects closely allied to that of the neighbouring desert regions of Central Asia The desert district of the Indian Sub-region includes the narrow strip of coast land to the north of the Persian Gulf, the Punjab, Rajputana, and the northern part of the Bombay Presidency. The greater part of the peninsula of India south of the great plains is occupied by the high, and rather dry, plateau of the Deccan and of Central India, which is covered with a thin and scanty jungle. The southern slopes of the western Ghats and the greater part of Ceylon enjoy an abundant rainfall, and are clothed with a tropical forest, in consequence of which their faunas present many points of resemblance both to each other and also to that of the Malayan Subregion, which has similar physical conditions.
Our knowledge of the mammals of this and the next Sub-region is very fairly complete, owing to the excellent handbook recently published by Mr. W. T. Blanford (2).
The Pangolin (Manis), which, with slight specific modifications, is also found in all the other Sub-regions as well as in the Ethiopian Region, is here the sole representative of the Edentates. The Sub-region is well provided with members of the various families of Ungulates. Three peculiar genera of Antelopes, which are not found beyond the limits of the Sub-region, have been already mentioned; other genera, such as the Gazelles (Gazella), the Goats (Capra), and the Sheep (Ovis), are found in other parts of the world as well as in this Sub-region, but are absent from the remaining Sub-regions.
All the families of Ungulates are common to this and the Ethiopian Region, except the Deer-family (Cervidm), the entire absence of which from Africa south of the Atlas has already been commented upon.
The Rodents do not present any marked features of interest in this Sub-region. One genus, Platacanthomys, a small dormouse-like member of the family Muridm, is found only in the hills of Southern India, otherwise the genera are mostly wide-spread forms.
Among the Carnivores the Cats are numerous and large. This Sub-region is the proper home of the Tiger, which, however, has extended itself throughout the whole Region, and even across its boundaries westwards into Persia and Trans-Caspia, and eastwards far into China and Manchuria. The Lion, too, which is essentially an animal haunting dry and comparatively barren countries, is a member of this division of the Indian fauna. It was formerly much more abundant in the peninsula, but