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The true Deer (Cervus), which we come to next, form the most numerous genus of the family, being about twenty-two in number. They are about equally divided between the Palæarctic and the Oriental Regions, with one representative, the Wapiti (C. canadensis) in the Nearctic Region. This occurrence is exactly in a line with that of the stray species of Sheep (Ovis), Bison (Bos), and Mountain Antelope (Haploceros) in the same Region, but is not sufficient, supported though it may be by other similar facts, to convince us of the necessity of recognizing a “Holarctic” Region. It should be stated also that typical Cervus is essentially characteristic of the Palæarctic Region, throughout which (with the above-mentioned exception of the Wapiti) the members of this splendid group of animals are distributed, whilst the sub-genera Axis, Rusa, and Rucervus take its place in the Oriental Region.

The Muntjacs (Cervulus) embrace about five species essentially Oriental, although two of them intrude within the bounds of the Palæarctic Region.

In the curious form Elaphodus we meet with a Deer with a tufted head which nearly conceals its minute antlers, restricted to the northern portion of the Palearctic Region, and leading us on to the Water-Deer (Hydrelaphus) of Southern China, in which the antlers are absolutely wanting.

Of the Roes (Capreolus) there seem to be three local races, which are often considered as so many species. These allied forms range over the whole extent of the Palæarctic Region.

We now come to that strange animal the Milou (Eluphurus) which has been sometimes associated with

the true Cervi, but which, as has been recently pointed out by Mr. Lydekker, possesses essentially distinctive characters in its remarkable horns, large and spreading hoofs, and long tail, besides other peculiarities. Mr. Lydekker is of opinion that the genus “has nothing to do with any of the living Old World Deer except the Roes, whilst its alliance with the American Deer (Cariacus) seems to be close.” If such be the case its patria is indeed remarkable, for, though only yet certainly known from captive specimens obtained in the Imperial Park, near Pekin, it is said to have been originally brought from Kashgaria, and must therefore be a Palearctic form.

The second section of the sub-family Cervine contains the American Deer of which two genera are usually recognizedCariacus 1 and Pudua-containing altogether at least twenty or twenty-one species, which are distributed throughout the Nearctic and Neotropical Regions. As all naturalists agree they form a very natural group, connected by many common characters which separate them from all the existing Deer of the Old World, although the fossil genus Anoglochis, formerly found in Western Europe, seems to have been a closely allied form. As in the case of Cervus the sub-divisions of Cariacus have special areas of distribution, Dorcelaphus being the inost northern form, whilst Blastocerus, Xenelaphus, and Subulo take its place in South America. The small Deer

1 We regret not to be able to follow Mr. Lydekker in using the generic term Mazama for this group. Mazama is a term which has already been most carefully studied and condemned by the late Professor Baird (" North American Mammals," p. 665) to be rejected for vagueness. Its author, Rafinesque, seems to have been an erratic person whose writings should be held to be of no authority whatever, and it is very doubtful whether any of his names, which were mainly based on the phantoms of his own imagination, should be employed in Science.

of the genus Pudua, distinguished from Cariacus by its remarkable foot-structure, consists of two species, one from Chili and Western Patagonia and the other from the high Andes of Ecuador.

The Musk-Deer which constitute a second well-defined sub-family of the Cervide and should perhaps even be recognized as a different family, contains only the genus Moschus, with two species, which are restricted to the Palæarctic Region.

SECTION XI.—DISTRIBUTION OF CHEVROTAINS

The Tragulidæ, or Chevrotains, consist of a few animals of small size, often known as Moose-Deer, which are intermediate in structure between the Deer, the Camels, and the Pigs. There are only two known genera of these animals at present existing, of which one (Tragulus), with about five species, belongs to the Oriental Region and the other (Hyomoschus), with a single species, is peculiar to Western Africa. The latter form is closely allied, if not identical with the extinct Dorcatherium of the tertiaries of the Old World, and is placed by some authorities in the same genus. Other extinct forms of small Ungulates serve to connect the Chevrotains, in former epochs, with the Deer.

SECTION XII.—DISTRIBUTION OF THE CAMELS

The forms of the Camel family now existing are two only, the true Camels of the Old World and the Lamas of the New. These are now separate in structure as in locality, but seem to be alike descendants of a group of extinct Camel-like ancestors formerly found in North America. The two species of Camelus now living are the One-humped Camel (C. dromedarius) and the Two-humped or Bactrian Camel (C. bactrianus) both of which are now best known in a domestic state. Indeed the original home of the One-humped Camel has not yet been certainly ascertained, although it is usually supposed to have been Arabia, where wild Camels are said to have existed about the commencement of the present epoch. We may therefore, perhaps, class the Arabian Camel as an Ethiopian type. But the true home of the Bactrian or Two-humped Camel is certainly the great deserts of Central Asia, where specimens of the wild species have been obtained both by Russian and English explorers. We may therefore place the Bactrian Camel as a Palearctic animal.

The two wild species of Lama—the Huanaco and Vicuna—are found only in the temperate portions of the Neotropical Region; from one or both of these are descended the Lamas and Alpacas of domesticity. The Lamas may consequently be classed as an indigenous form of the Neotropical Region.

SECTION XIII.—DISTRIBUTION OF SWINE-LIKE

UNGULATES

At the end of the great Ungulate series we come to the Swine or Swine-like mammals, of which the existing forms are usually assigned to four separate families, the Hippopotamuses, Wart-Hogs, true Swine, and Peccaries. Most of these forms, except the Swine, have in these days a very limited distribution, but in former days the whole series was connected, in locality as in form, by hosts of ancestors now extinct.

The Hippopotamidæ, or Hippopotamuses, formerly widely-spread over the whole world, have now only two surviving species, the larger Hippopotamus amphibius, which is met with in nearly all the great African lakes and rivers, and the smaller Liberian Hippopotamus (H. liberiensis) which has hitherto been found only in one of the rivers of Liberia. As regards the existing creation, therefore, this peculiar form of Ungulates must be regarded as strictly Ethiopian.

The second family of Swine-like Ungulates—the Warthogs (Phacochorida)—is also entirely confined to Africa, where two species are widely distributed from Upper Nubia, throughout Eastern Africa, down to the Cape Colony.

The true Suidæ, or Swine, to which the Wart-hogs are indeed closely allied, embrace three genera–Sus, Potamochoerus and Babirussa. The typical Swine (Sus) are found in the southern part of the Palæarctic and the Oriental Regions, extending from Southern Europe, through Western Asia into India and the islands of the Indian Archipelago. It is difficult in many cases to ascertain what are the real wild species of this group, the domestic forms having varied much under domestication for many ages and having been carried by man all over the world. It is probable that the Swine of New Guinea-the so-called Sus papuensis—and those of other Eastern islands may be descendants of domestic or semi-domestic animals.

In the Ethiopian Region the place of Sus is taken by the River-hog (Potamochoerus), with a slightly different

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