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Oriental regions; but they only occur in the Ethiopian region in South Africa and in the Deserts of the north, which more properly belong to the Palæarctic region. They are absent from the Malayan, and also from the Indo-Chinese sub-regions; except that they extend from the north of China to Amoy and Formosa, and into the temperate highlands of the Western Himalayas. The curious Gymnura (1 species) is found in Borneo, Sumatra, and the Malay peninsula.
Extinct Species. The common hedgehog has been found fossil in several Post-tertiary deposits, while extinct species occur in the lower Miocene of Auvergne and in some other parts of Europe. Many of these remains are classed in different genera from the living species ;-(Amphechinus, Tetracus, Galerix.)
FAMILY 18.–CENTETIDÆ. (6 Genera, 10 Species.)
The Centetidæ are small animals, many of them having a spiny covering, whence the species of Centetes have been called Madagascar hedgehogs. The genera Centetes (2 species), Hemicentetes (1 species), Ericulus (1 species), Echinops (3 species), and the recently described Oryzorictes (1 species), are all exclusively inhabitants of Madagascar, and are almost or quite tail-less. The remaining genus, Solenodon, is a more slender and active animal, with a long, rat-like tail, shrew-like head, and coarse fur; and the two known species are among the very few indigenous mammals of the West Indian islands, one being found in Cuba (Plate XVII., vol. ii., p. 67), the other in Hayti. Although presenting many points of difference in detail, the essential characters of this curious animal are, according to Professors Peters and Mivart, identical with the rest of the Centetidæ. We have thus a most remarkable and well-established case of discontinuous distribution, two portions of the same family
being now separated from each other by an extensive continent, as well as by a deep ocean.
Extinct Species.—Remains found in the Lower Miocene of the South of France are believed to belong to the genus Echinops, or one closely allied to it.
FAMILY 19.—POTAMOGALIDÆ. (1 Genus, 1 Species,)
The genus Potamogale was founded on a curious, small, otterlike animal from West Africa, first found by M. Du Chaillu ut the Gaboon, and afterwards by the Portuguese at Angola. Its affinities are with several groups of Insectivora, but it is sufficiently peculiar to require the establishment of a distinct family for its reception. (Plate V., vol. i., p. 264.)
FAMILY 20. CHRYSOCHLORIDÆ. (2 Genera, 3 Species.)
The Chrysochloride, or golden moles, of the Cape of Good Hope have been separated by Professor Mivart into two genera, Chrysochloris and Chalcochloris. They are remarkable mole-like animals, having beautiful silky fur, with a metallic lustre and changeable golden tints. They are peculiar to the Cape district, but one species extends as far north as the Mozambique territory. Their dentition is altogether peculiar, so as to completely separate them from the true moles.
FAMILY 21.-TALPIDÆ. (8 Genera, 19 Species.
The Moles comprise many extraordinary forms of small mammalia especially characteristic of the temperate regions of the northern hemisphere, only sending out a few species of Talpa along the Himalayas as far as Assam, and even to Tenasserim, if there is no mistake about this locality ; while one species is found in Formosa, the northern part of which is almost as much Palæarctic as Oriental. The genus Talpa (7 species), spreads over the whole Palæarctic region from Great Britain to Japan; Scaptochirus (1 species) is a recent discovery in North China; Condylura (1 species), the star-nosed mole, inhabits Eastern North America from Nova Scotia to Pennsylvania; Scapanus (2 species) ranges across from New York to St. Francisco; Scalops (3 species), the shrew-moles, range from Mexico to the great lakes on the east side of America, but on the west only to the north of Oregon. An allied genus, Myogale (2 species), has a curious discontinuous distribution in Europe, one species being found in South-East Russia, the other in the Pyrenees (Plate II., vol. i., p. 218). Another allied genus, Nectogale (1 species), has recently been described by Professor Milne-Edwards from Thibet. Urotrichus is a shrew-like mole which inhabits Japan, and a second species has been discovered in the mountains of British Columbia; an allied form, Uropsilus, inhabits East Thibet. Anurosorex and Scaptonyx, are new genera from North China.
Extinct Species.—The common mole has been found fossil in bone-caves and diluvial deposits, and several extinct species of mole-like animals occur in the Miocene deposits of the South of France and of Germany. These have been described under the generic names Dimylus, Geotrypus, Hyporissus, Galeospalax; while Palæospalax has been found in the Pliocene forest-beds of Norfolk
and Ostend. Species of Myogale also occur from the Miocene downwards.
FAMILY 22.-SORICIDÆ. (1 Genus, 11 Sub-genera, 65 Species.)
The Shrews have a wide distribution, being found throughout every region except the Australian and Neotropical ; although, as a species is found in Timor and in some of the Moluccas, they just enter this part of the former region, while one found in Guatemala brings them into the latter. A number of species have recently been described from India and the Malay Islands, so that the Oriental region is now the richest in shrews, having 28 species; the Nearctic comes next with 24; while the Ethiopian has 11, and the Palæarctic 10 species. The sub-genera are Crossopus, Amphisorer, Neosorex, Crocidura, Diplomesodon, Pinulia, Pachyura, Blarina, Feroculus, Anausorex.
Extinct Species.-Several species of Sorex have been found fossil in the Miocene of the South of France, as well as the extinct genera Mysarachne and Plesiosorex ; and some existing species have occurred in Bone Caves and Diluvial deposits.
General Remarks on the Distribution of the Insectivora. The most prominent features in the distribution of the Insectivora are,-their complete absence from South America and Australia; the presence of Solenodon in two of the West Indian islands while the five allied genera are found only in Madagascar; and the absence of hedgehogs from North America. If we consider that there are only 135 known species of the order, 65 of which belong to the one genus Sorex; while the remaining 26 genera contain only 70 species, which have to be classed in 8 distinct families, and present such divergent and highly specialized forms as Galeopithecus, Erinaceus, Solenodon, and Condylura, it becomes evident that we have here the detached fragments of a much more
extensive group of animals, now almost extinct. Many of the forms continue to exist only in islands, removed from the severe competition of a varied mammalian population, as in Madagascar and the Antilles ; while others appear to have escaped extermination either by their peculiar habits—as the various forms of Moles; by special protection-as in the Hedgehogs; or by a resemblance in form, coloration, and habits to dominant groups in their own district—as the Tupaias of Malay which resemble squirrels, and the Elephant-shrews of Africa which resemble the jerboas. The numerous cases of isolated and discontinuous distribution among the Insectivora, offer no difficulty from this point of view; since they are the necessary results of an extensive and widelyspread group of animals slowly becoming extinct, and continuing to exist only where special conditions have enabled them to maintain themselves in the struggle with more highly organized forms.
The fossil Insectivora do not throw much light on the early history of the order, since even as far back as the Miocene period they consist almost wholly of forms which can be referred to existing families. In North America they go back to the Eocene period, if certain doubtful remains have been rightly placed. The occurrence of fossil Centetidæ in Europe, supports the view we have maintained in preceding chapters, that the existing distribution of this family between Madagascar and the Antilles, proves no direct connection between those islands, but only shows us that the family once had an extensive range.
FAMILY 23.-FELIDÆ. (3 Genera, 14 Sub-genera, 66 Species.)
The Cats are very widely distributed over the earth-with the exception of the Australian region and the island sub-region