the tapirs and camels; while others once confined to Europe and Asia have found a refuge in Africa,-as the hippopotamus and giraffe; so that in no other order do we find such striking examples of those radical changes in the distribution of the higher animals which were effected during the latter part of the Tertiary period. The present distribution of this order is, in fact, utterly unintelligible without reference to the numerous extinct forms of existing and allied families; but as this subject has been sufficiently discussed in the Second Part of this work (Chapters VI. and VII.) it is unnecessary to give further details here.

Order VIII.—PROBOSCIDEA.

FAMILY 53. ELEPHANTIDÆ. (1 Genus, 2 Species.)

The elephants are now represented by two species, the African, which ranges all over that continent south of the Sahara, and the Indian, which is found over all the wooded parts of the Oriental region, from the slopes of the Himalayas to Ceylon, and eastward, to the frontiers of China and to Sumatra and Borneo. These, however, are but the feeble remnants of a host of gigantic creatures, which roamed over all the great continents except Australia during the Tertiary period, and several of which were contemporary with man.

Extinct Elephants.—At least 14 extinct species of Elephas, and a rather greater number of the allied genus Mastodon (distinguished by their less complex grinding teeth) have now been

discovered. Elephants ranged over all the Palearctic and Nearctic regions in Post-Pliocene times; in Europe and Central India they go back to the Pliocene; and only in India to the Upper Miocene period; the number of species increasing as we go back to the older formations.

In North America two or three species of Mastodon are Postpliocene and Pliocene; and a species is found in the caves of Brazil, and in the Pliocene deposits of the pampas of La Plata, of the Bolivian Andes, and of Honduras and the Bahamas. In Europe the genus is Upper Miocene and Pliocene, but is especially abundant in the former period. In the East, it extends from Perim island to Burmah and over all India, and is mostly Miocene, but with perhaps one species Pliocene in Central India.

An account of the range of such animals as belong to extinct families of Proboscidea, will be found in Chapters VI. and VII.; from which it will be seen that, although the family Elephantidæ undoubtedly originated in the Eastern Hemisphere, it is not improbable that the first traces of the order Proboscidea are to be found in N. America.

Order IX-HYRACOIDEA.

FAMILY 54.-HYRACIDÆ. (1 Genus. 10-12 Species.)

NEOTROPICAL

GENERAL DISTRIBUTION.

NEARCTIC

PALEARCTIC ETHIOPIAN

ORIENTAL

AUSTRALIAN

SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS.

The genus Hyrax, which alone constitutes this family, consists of small animals having the appearance of hares or marmots, but which more resemble the genus Rhinoceros in their teeth and skeleton. They range all over the Ethiopian region, except Madagascar; a peculiar species is found in Fernando Po, and they just enter the Palearctic as far as Syria. They may therefore be considered as an exclusively Ethiopian group. In Dr. Gray's

last Catalogue (1873) he divides the genus into three—Hyrax, Euhyrax, and Dendrohyrax—the latter consisting of two species confined apparently to West and South Africa.

No extinct forms of this family have yet been discovered; the Hyracotherium of the London clay (Lower Eocene) which was supposed to resemble Hyrax, is now believed to be an ancestral type of the Suidæ or swine.

Order X-RODENTIA.

FAMILY 55.—MURIDÆ. 37 Genera, 330 Species.)

NEOTROPICAL

GENERAL DISTRIBUTION.

NEARCTIC

ORIENTAL AUSTRALIAN

PALEARCTIC ETHIOPIAN SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS.

1.2.3.4 1.2.3.4 1.2.3.4 1.2.3.4 1.2.3.4 4.2

The Muridæ, comprising the rats and mice with their allies, are almost universally distributed over the globe (even not reckoning the domestic species which have been introduced almost everywhere by man), the exceptions being the three insular neither groups belonging to the Australian region, from none of which have any species yet been obtained. Before enumerating the genera it will be as well to say a few words on the peculiarities of distribution they present. The true mice, forming the genus Mus, is distributed over the whole of the world except N. and S. America where not a single indigenous species occurs, being replaced by the genus Hesperomys; five other genera, comprehending all the remaining species found in South America are peculiar to the Neotropical region. Three genera are confined to the Palearctic region, and three others to the Nearctic. No less than twelve genera are exclusively Ethiopian, while only three are exclusively Oriental and three Australian.

Mus (100-120 sp.) the Eastern Hemisphere, but absent from the Pacific and Austro-Malayan Islands, except Celebes and Papua; Lasiomys (1 sp.) Guinea; Acanthomys (5-6 sp.) Africa, India,and

tem A.

N. Australia; Cricetomys (1 sp.) Tropical Africa; Saccostomus (2 sp.) Mozambique; Cricetus (9 sp.) Palæarctic region and Egypt; Cricetulus (1 sp., Milne-Edwards, 1870) Pekin; Pseudomys (1 sp.) Australia; Hapalotis (13 sp.) Australia; Phlœomys (1 sp.) Philippines; Platacanthomys (1 sp., Blyth, 1865) Malabar; Dendromys (2 sp.) S. Africa; Nesomys (1 sp. Peters, 1870) Madagascar; Steatomys (2 sp.) N. and S. Africa; Pelomys (1 sp.) Mozambique ; Reithrodon (9 sp.) N. America, Lat. 29° to Mexico, and south to Tierra del Fuego; Acodon (1 sp.) Peru; Myxomys (1 sp.) Guatemala; Hesperomys (90 sp.) North and South America; Holochilus (4 sp.) South America; Oxymycterus (4 sp.) Brazil and La Plata ; Neotoma (6 sp.) U.S., East coast to California; Sigmodon (2 sp.) Southern United States; Drymomys (1 sp.) Peru; Neotomys (2 sp.) S. America; Otomys (6 sp.) S. and E. Africa; Meriones = Gerbillus (20-30 sp.) Egypt, Central Asia, India, Africa; Rhombomys (6 sp.) S. E. Europe, N. Africa, Central Asia; Malacothrix (2 sp.) South Africa; Mystromys (1 sp.) South Africa; Psammomys (1 sp.) Egypt; Spalacomys (1 sp.) India; Sminthus (1-3 sp.) East Europe, Tartary, Siberia; Hydromys (5 sp.) Australia and Tasmania; Hypogeomys (1 sp., Grandidier, 1870) Madagascar; Brachytarsomys (1 sp., Günther, 1874) Madagascar; Fiber (2 sp.) N. America to Mexico; Arvicola (50 sp.) Europe to Asia Minor, North Asia, Himalayas, Temp. N. America; Cuniculus (1 sp.) N. E. Europe, Siberia, Greenland, Arctic America; Myodes (4 sp.) Europe, Siberia, Arctic America, and Northern United States; Myospalax = Siphneus (2 sp.) Altai Mountains and N. China1; Lophiomys (1 sp.) S. Arabia, and N. E. Africa; Echiothrix (1 sp.) Australia.

Extinct Muride.-Species of Mus, Cricetus, Arvicola, and Myodes, occur in the Post-Pliocene deposits of Europe; Arvicola, Meriones, and the extinct genus Cricetodon, with some others, in the Miocene.

1

In North America, Fiber, Arvicola, and Neotoma, occur in caves;

Myospalax has hitherto formed part of the next family, Spalacidæ ; but a recent examination of its anatomy by M. Milne-Edwards shows that it belongs to the Muridæ, and comes near Arvicola.

an extinct genus, Eumys, in the Upper Miocene of Dakota, and another, Mysops, in the Eocene of Wyoming.

In South America Mus, or more probably Hesperomys, is abundant in Brazilian caverns, and Oxymycterus in the Pliocene of La Plata; while Arvicola is said to have occurred both in the Pliocene and Eocene deposits of the same country.

FAMILY 56.-SPALACIDE. (7 Genera, 17 Species.)

GENERAL DISTRIBUTION.

NEOTROPICAL NEARCTIC PALEARCTIC ETHIOPIAN

ORIENTAL AUSTRALIAN

SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS.

The Spalacidæ, or mole-rats, have a straggling distribution over the Old World continents. They are found over nearly the whole of Africa, but only in the South-east of Europe, and West of Temperate Asia, but appearing again in North India, Malacca, and South China. Ellobius (1 sp.), is found in South Russia and South-west Siberia; Spalax (1 sp.), Southern Russia, West Asia, Hungary, Moldavia, and Greece (Plate II., vol. i. p. 218); Rhizomys (6 sp.), Abyssinia, North India, Malacca, South China; Heterocephalus (1 sp.), Abyssinia; Bathyerges (= Orycterus 1 sp.), South Africa; Georychus (6 sp.), South, Central, and East Africa; Heliophobus (1 sp.), Mozambique.

The Jerboas, or jumping mice, are especially characteristic of the regions about the eastern extremity of the Mediterranean, being found in South Russia, the Caspian district, Arabia, Egypt, VOL. II.-16