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outside the limits of this Sub-region. A fifth endemic genus of rodents is Ellobius, which is thoroughly adapted to a subterranean life, having very short limbs and tail, and rudimentary external ears. The only two known species of this genus are restricted to the Eremian Sub-region.
The Eremian Carnivora, as is usually the case with this group, are mostly widespread, and this is also the case with the Bats. The Insectivora are not very numerous, but one genus is peculiar to the Sub-region; this is Diplomesodon, a little shrew-like animal of terrestrial habits found in the Kirghiz steppes. Another genus, Macroscelides (the Elephant-shrew), though typically Ethiopian, has one species that extends into this Sub-region in Algeria and Tunis.
The Monkeys are represented in the Eremian Subregion by one species only, the well-known Barbary Ape, (Macacus inuus), which is found in Algeria and Morocco.
The genera that occur in the Eremian Sub-region are shown in the following table, which may be compared with the corresponding table appended to the Europasian Subregion :
SECTION VI.—THE CHINESE SUB-REGION
The Chinese Sub-region bears the same relation to the Oriental Region as the Desert Sub-region does to the Ethiopian Region, and the number of genera of Mammals that are common to it and the Oriental Region is considerable.
On the whole, too, this is the most specialized of all the Palæarctic Sub-regions; six genera out of a total number of sixty being endemic, and several others only just crossing its borders. This Sub-region contains within its limits the highest tableland on the face of the globe, that of Tibet, the zoology of which is not so well known as it should be, owing to the persistent exclusion of European travellers from its limits.
What knowledge we have of the Tibetan fauna relates chiefly to the larger animals, and among these are several very interesting and peculiar forms. It is, therefore, probable that when more about this Region is known, many novelties will be discovered among the smaller animals
The Ungulates of the Chinese Sub-region show no genera which are absolutely confined to it, but a curious little deer with short straight antlers (Elaphodus) is highly characteristic of it, although it extends into the outskirts of the Oriental Region. Another peculiar genus is the Tibetan antelope (Pantholops), well known to Indian sportsmen, which is found only at great heights on the Tibetan plateau. A third genus, also of great interest, is the Takin (Budorcas), a large bovine animal with horns somewhat resembling those of the South African Gnu; this is also found only among the higher mountain ranges, and is probably confined to the Sub-region.
Among the Rodents of this Sub-region there are two genera peculiar. One of these is Eupetaurus, a flying squirrel, which, unlike all others of the same group, lives in a part of the world practically devoid of forests. It is as yet known only from the extreme north-western part of the Indian Empire, but doubtless has a wider range. The second endemic genus, Typhlomys, has been formed for the reception of a curious, almost blind Mouse of Northern China.
Among the Carnivora of the Chinese Sub-region the only genus of very special interest is Æluropus, which has already been mentioned in the general account of the Region. The Insectivora of this Sub-region are numerous, comprising as they do ten genera, of which three are endemic. These are all of them Shrews, two of which, Chimarrhogale and Nectogale, are aquatic forms with webbed toes, while the third, Anurosorex, is probably fossorial, All the Bats belong to fairly wide-spread forms.
Finally, there are two genera of Monkeys represented in this Sub-region, Macacus and Semnopithecus, but these forms belong strictly to the Oriental Region.
Below is a table of the genera of the Sub-region, arranged as in the foregoing Sub-regions, which shows what a considerable number of forms are common to this and the Oriental Region.
SECTION VII.-THE PAST HISTORY OF THE
Although the palæontological history of Europe, so far as it has been worked out, has been very thoroughly investigated, our knowledge of its extinct mammals, at any rate, is not to be compared with that which has been acquired in the Nearctic Region. This is probably due, to a great extent, to the comparative rarity on this side of the Atlantic of fresh-water lake deposits, the examination of which, in North America, has produced such astonishing results.
Passing over the Mesozoic Mammals, which throw very little light on any of the problems involved in the present case, we find in the earliest Eocene beds scanty remains of a fauna containing hardly any members of the existing orders of Mammals. In their place is a series of forms closely resembling one another in possessing five-toed and
plantigrade extremities, furnished with neither hoofs nor claws, but with structures somewhat intermediate between the two. Nevertheless, even among these primitive mammals, it is possible to recognize the germs of the marked characters which at the present day separate the various Orders. In North America, in beds of the corresponding age, a much more ample stock of remains of a similar fauna is met with. Later on, in the Upper Eocene beds a much larger number of Mammals appears, this fauna containing at least a hundred genera, most of them of large size, whereas to-day the European Mammal-fauna consists only of fifty-four genera, and of these more than half are of small size. At this epoch slight distinctions between the European and American forms begin to appear, showing that even at these early times there was a commencing separation between the two great continents. In the earlier part of the Miocene age, so far as we know, no very great changes take place, but at the end of Miocene time we find in several localities wonderful assemblages of fossil Mammals in great abundance and in an excellent state of preservation, which enable us to make a better comparison. Such localities have been discovered at Pikermi in Greece, in the island of Samos in the Ægean Sea, at Maragha in Persia, and, perhaps the most important of all of them, in the Sivalik Hills at the southern base of the Himalayas.
This fauna bears a close resemblance to that of the Ethiopian Region in the present state, especially as regards the presence of Giraffes, Gazelles, and other Ungulates. North of the Alps this fauna, although represented, is not nearly so rich, many of the Antelopes and Giraffes being absent and being replaced by various forms of Deer