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discovered in Southern China. Another small Deer, for which a separate genus (Hydropotes) has been rightly formed, has no trace of antlers at all, and in other respects differs much from the remaining members of the family. This form is entirely confined to Southern China. A third peculiar genus, belonging to the Bovidæ, is the Takin (Budorcas). This ox-like Antelope is also found in Western Tibet, but extends its range southwards to the Mishmi country in the north of Assam. The Takin is one of the very few of the larger ruminants that has never been met with or shot by European sportsmen, and our knowledge of it is entirely derived from the natives.

The Burmo-Chinese, like the Malayan Sub-region, is the most frequented haunt of the Squirrel family (Sciuridæ). No less than thirty-two species, referable to the genera Sciurus (the true Squirrel) and to Pteromys and Sciuropterus, the Flying Squirrels, are found here alone. The only Rodent supposed to be truly endemic is Hapalomys, a long-tailed Rat found in Burma.

The Burmo-Chinese Carnivores do not call for any special remark; one genus alone (Helictis) is strictly endemic. It contains three or four species of small badger-like animals with arboreal habits.

Among the insectivores of this Sub-region only one genus is endemic. This is Soriculus, containing some small shrew-like mammals found only in Sikkiin and Assam. Several species of Mole (Talpa), as also Anurosorex, and Chimarrhogale, belonging to the Shrew family (Soricidæ), extend from the Palæarctic Region into this Sub-region, but no farther.

The Bats of Burmo-China need not detain us long; most of the genera are widely spread, and a very large

number of them extend across Wallace's line into the Austro-Malayan islands—a distribution shared by hardly any other of the Oriental genera of mammals.

One of the Slow Lemurs, Nycticebus, is common to this and the Malayan Sub-region; it bears a certain resemblance to the Indian genus Loris, but is distinguished by its somewhat stouter aspect and its still more sluggish habits.

Among the Monkeys of this Sub-region, in addition to the two genera Macacus and Semnopithecus, inhabiting also the Indian Sub-region, a genus of the anthropoid Apes occurs. This is Hylobates, members of which are commonly known as Gibbons; they are slender animals, with very long limbs and no tail, and are entirely restricted to the forest districts, being exclusively arboreal in their mode of life.

The following summary of the Burmo-Chinese genera of mammals has been drawn up exactly in the same way as the previous list, except that under an additional heading, “ Australian,” are placed two genera common to the Oriental and Australian Sub-regions :

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SECTION VI.—THE MALAYAN SUB-REGION

The Malayan Sub-region lies entirely within the tropics, and almost the whole of it is covered with a luxuriant tropical jungle. It is here, consequently, that we find the Oriental fauna in its highest state of development, and with the least admixture of forms belonging to other Regions. With the exception of the Malay Peninsula, the whole of this Sub-region consists of islands, which, however, are separated from the main continental mass by comparatively shallow water, so that an elevation of 100 fathoms would obliterate the whole of the sea between the various islands, leaving them connected with one another and with the Asiatic continent. There can be no doubt that these islands, all of which have very rich faunas, have been stocked from the mainland, and that a careful study and comparison of their component parts would go far to enable us to trace out the past history of the Region, and to find out what changes have taken place from time to time in the distribution of land and sea.

If a careful analysis of the mammalian genera of the Sub-region be made, it will be found that the greater number of the genera found on the mainland extend to all the three larger islands, Sumatra, Java, and Borneo, and that of the remaining genera the larger proportion are common to the Malay Peninsula, Sumatra, and Borneo, and are not found in Java. This would seem to indicate that Java was separated from the mainland before Sumatra and Borneo, and this view is further borne out by the fact that individual species of a genus are frequently common to the Malay Peninsula, Sumatra, and Borneo,

whereas in Java they are replaced by slightly different forms. The Philippines, though connected with Borneo by two chains of islands, so that the straits separating the group from Borneo are nowhere very wide, contain a poor mammal-fauna as compared with Borneo. Only about fourteen genera, exclusive of bats, have reached these islands, and, with one exception, these are all widespread. But it must be recollected that the Mammal-fauna of the Philippines is still very imperfectly known.

The following table gives the figures relating to the distribution of the genera within the Sub-region (excluding bats):

Number of genera that occur in

(1) The Malay Peninsula, Sumatra, Borneo, and Java.
(2) The Malay Peninsula, Sumatra, and Borneo . .
(3) The Malay Peninsula and Borneo alone. . .
(4) The Malay Peninsula, Sumatra, and Java. .
(5) The Malay Peninsula and Java alone . . .

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As regards the Philippines, the total number of mammal genera (exclusive of bats) is fourteen, thirteen of which occur also in the Malay Peninsula and islands; one is confined to the Philippines alone; in addition five Malayan genera reach Palawan, a large island lying between Borneo and the Philippines.

Although the Malayan Sub-region does not contain any endemic genera of Ungulates, there is one form the distribution of which is so remarkable that special attention must be drawn to it. This is the Tapir, one species of which is found in the Malay Peninsula, Sumatra, and Borneo, the only other Tapirs now existing in the world being met with in Central and Southern America. This is one of the most interesting cases known of what is termed "discontinuous " distribution, but the explanation of it is not very difficult. If we turn to the records of palæontology, we find undoubted remains of the members of the genus Tapirus recorded in the Miocene formation of France, in North America, and also in the Pliocene of China. There can be little doubt, therefore, that the Tapir, which is a harmless beast, destitute of all means of offence and defence, has been driven out of these northern countries into the tropical forests of South America and Malaya, where the absence of competition has enabled it to survive.

1 This calculation was made before Mr. John Whitehead's great discoveries in the highlands of North Luzon (see Ann. N. H., ser. 6, vol. xvi., p. 160, and Trans. Zool. Soc., vol. xiv., pt. 6) were announced by Mr. Thomas. These embrace five new generic forms of rodents, and there are probably more to follow.

Among the Malayan Rodents we find the squirrels (Sciuridx) even more abundant than in the last Subregion. Two of the species belong to a separate genus (Rhithrosciurus) which does not occur elsewhere. There are also two endemic genera of rats (Muridx) — one (Phlæomys) from the Philippines, the other (Pithechirus) from Sumatra and Java.

A genus of Porcupines (Trichys), which differs from Atherura in several important cranial characters, is confined to Borneo.

Three genera of Malayan Carnivores are worthy of special mention. One of these is Hemigale, not very far removed from the Palm-cats, with two species, a second one having been recently discovered by Mr. Hose in the mountains of Borneo. The second is Cynogale, also belonging to the same family. The latter, which is semiaquatic in its habits, and bears a superficial resemblance

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