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stiff hairs along the sides of its feet and tail, which are doubtless of great assistance to it in swimming. Another shrew, Nectogale, found only in Tibet, is still better provided for an aquatic existence, as it has webs between the toes of both fore and hind limbs. The most remarkable endemic representative of the family of Moles in the Palæarctic Region is the Desman, Myogale, of which there are two species, one found in the Pyrenees, and the other in the streams and lakes of South-Eastern Russia. The external appearance of these animals, however, resembles much more that of a Shrew than that of a Mole.

Considering that the whole of this Region lies within the temperate zone, the number of its Bats is considerable, although they mostly belong to widespread genera. The Monkeys are represented in the Palæarctic Region by outlying species of two genera, Macacus and Semnopithecus, which are both abundant in the Oriental Region. To the former of these belongs the well-known Barbary ape (Macacus inuus), which inhabits the Rock of Gibraltar and the Barbary States of Northern Africa, as well as several species of Eastern Asia. Another Macaque (M. tcheliensis) is enabled by its thickened fur to endure the extremely severe climate of the mountains north of Pekin, and is probably the most northern monkey now living.

SECTION III.—SUB-DIVISION OF THE PALÆARCTIC

REGION

The sub-divisions of the Palæarctic Region recognized by Wallace are four in number; these are—First, the European Sub-region, which includes Europe north of the

Alps and the continuing mountain ranges that form the backbone of the continent; secondly, the Mediterranean Sub-region, which consists of the remainder of Europe, Northern Africa, and Western Asia as far as the borders of the Oriental Region; thirdly, the Siberian Sub-region, which includes not only the country from which it takes its name, but also the whole of the desert region of Central Asia, and reaches as far south as the Himalayas; fourth and last, the Manchurian Sub-region, containing the greater part of China proper and Manchuria together with Japan.

These Sub-regions, however, do not appear to represent the true faunal divisions of the Palæarctic Sub-region quite adequately. In the first place, there seems to be a fairly continuous and unchanging fauna extending from the west of Europe all across Siberia and embracing the northern island (at any rate) of Japan. This wide area is still, to a great extent, covered with forest, and was, no doubt, mainly so beset until within comparatively recent times.

Again, Wallace's arrangement divides between two Subregions the vast extent of desert country that reaches from the Sahara through Egypt, Arabia, Persia, and Turkestan to Mongolia, which also appears to contain a fairly homogeneous fauna. Wallace's Manchurian Subregion, on the other hand, seems to be well established, and to be the most distinctive of all his Sub-regions, but as it only embraces a part of Manchuria, we prefer to call it the Chinese Sub-region.

We may, therefore, distinguish three Sub-regions in the Palearctic Region as follows:

1. The Europasian Sub-region, containing Europe, the

whole of Siberia north of the great mountain ranges together with the island of Saghalien, and perhaps, too, the Japanese island of Yezo. In this Sub-region must also be included Asia Minor, the Caucasus, and the Elburz mountains.

2. The Eremian Sub-region, including the north of Africa, Northern Arabia, the greater part of Persia and Afghanistan, and the great desert of Central Asia, extending from the steppes of Southern Russia as far as Manchuria.

3. The Chinese Sub-region, embracing the greater part of China proper, Southern Manchuria, and Japan, and extending westward to Western Tibet and the top of the southern slopes of the Himalayas.

The boundaries of these Sub-regions will be best understood by referring to the accompanying map (Plate VII., p. 196), in which they are approximately delineated; but it must be always understood that it is in most cases quite impossible to draw a hard and fast line as the boundary between two adjacent Regions on land.

SECTION IV.—THE EUROPASIAN SUB-REGION

The Europasian Sub-region contains the great temperate forest-area of the Northern Hemisphere. In its western part, at any rate, this has been considerably modified by the hand of man, but in primæval times the forests probably extended almost without break from the Bay of Biscay to Kamtchatka.

The Europasian fauna is not very rich; it comprises fifty-seven genera of Mammals, of which four only are

restricted to its boundaries. The endemic forms among the Ungulata are Capreolus, containing the Roe-deer, a single species of which is found throughout the whole extent of the Region; and Rupicapra, the Chamois, found only in the Pyrenees, Alps, Carpathians, and Caucasus. The single endemic rodent is the familiar Dormouse (Muscardinus), which is apparently confined to Europe. On the other hand, the little Water-shrew (Crossopus) extends from England to the Altai mountains.

There is a considerable number of genera common to the Europasian Sub-region and the Nearctic Region. With the exception, however, of two, the Elk and the Reindeer, these have mostly spread also into the other Palæarctic Sub-regions. On the whole the fauna of this Sub-region has little individuality, and calls for very few remarks as to its distinctness.

Appended is a list of the genera, drawn up in the same manner as in the previous tables.

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SECTION V.—THE EREMIAN SUB-REGION

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The Eremian or Desert Sub-region of the Palæarctic Region contains representatives of a larger number of genera than the Europasian, and a higher percentage of endemic forms, although even here we do not find so much individual character as in some of the Sub-regions previously treated of. A considerable number of the genera are common to this and the Ethiopian Region, which is, perhaps, not to be wondered at, considering the long land boundary which runs between them.

Among the Ungulates only one genus is confined to this Region—the Camel (Camelus), which is now found wild only in certain desert tracts of Central Asia, being elsewhere known only in a domesticated condition. But remains of animals of this genus have been found in comparatively recent beds both in India and Algeria. Except for this, other indications seem to point to the fact that the Camels must have had their origin in the New World, where they are now represented only by the Lamas. But remains of several allied genera of Camelidæ have been met with in the Tertiary beds of North America, where, however, they have been long extinct. Bubalis, which contains the Antelopes usually known as “Hartebeests,” and Hyrax (the Tree-conies) are common to this Sub-region and the Ethiopian Region. Among the Rodents no less than five genera are confined to the Sub-region, the most remarkable of these being, perhaps, the Jerboas, or Kangaroo-rats, as they are called, from having their hind legs elongated for jumping purposes. The four known genera of Jerboas, which contain a large number of species, are not found

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