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Palearctic and Oriental Regions, but with certainly one Nearctic representative, and two, or possibly three, in the Ethiopian Region. The true origin of our domestic cattle (Bos), is lost in obscurity, but is usually attributed to Palearctic ancestors, although the progenitor of the humped form, or Zebus, may have more probably been Oriental. The two Bisons belong, one to the Palearctic and one to the Nearctic Regions, and are very nearly allied. The Yak (Poephagus) is confined to the higher mountain ranges of Central Asia, and must be therefore reckoned as Palearctic. The characteristic Oriental forms of bovine animals are the Bantengs (Bibos), of which subgenus three species are commonly recognized. The Bantengs extend from the mountains of Northern India through the ranges of the Malay Peninsula into the Sondaic Islands. Of the Buffaloes (Bubalus) three species are commonly recognized, one of which is Indian, the parent of the well-known domestic form, while two, or perhaps three, other nearly allied species are peculiar to Africa. Finally, closely allied to the Buffaloes, and hardly distinguishable from them, we have the little Anoa of Celebes, and the lately discriminated Bubalus mindorensis of the Philippine Islands.

SECTION VIII.-DISTRIBUTION OF PRONGBUCKS

The second family of Artiodactyle Ungulates embraces only a single species strictly confined to the Nearctic Region, and constituting one of its most peculiar types. This is the Prongbuck (Antilocapra americana), of the western prairies of the United States, which (as was first

ascertained in this country) carries hollow horns, like those of the Bovida, but sheds them regularly every year, like the deciduous antlers of the Stags.

SECTION IX.-DISTRIBUTION OF GIRAFFES

The next family of Arctiodactyles, the Giraffidæ, consists likewise of what is called a monotypic form, embracing a single species only, and limited, in the present epoch, entirely to one Region of which it is one of the most characteristic animals. The Giraffe (Giraffa camelopardalis) is distributed over the greater part of Africa, from Senegal through the Southern Sahara to Upper Nubia, and thence southward throughout Eastern Africa in suitable localities to the Cape. So far as we know at present it is not found within the great wooded regions of the Congo valley and western coast, but is certainly met with on the Niger and on the Upper Gambia. As has recently been well shown by Mr. de Winton (P. Z. S. 1897, p. 273) the Giraffe presents us with two geographical forms, which may be designated either as species or sub-species. The Northern Giraffe (Giraffa camelopardalis typica) which is met with in Senegal and thence across the Sahara to Upper Nubia, Somaliland, and British East Africa is distinguished from the Southern Giraffe (Giraffa camelopardalis capensis) by several characters, especially by the great prominence of the third frontal horn which is barely apparent in the southern Giraffe. The Cape Giraffe seems to be met with in suitable localities all up the east coast into British East Africa, where it is stated that the two forms meet. More accurate information about the two forms of Giraffe

is, however, highly desirable, and the areas of the two sub-species require to be carefully studied.

SECTION X.-DISTRIBUTION OF DEER

The seventh family of Ungulates which we now come to, though it cannot rival the Bovida, is likewise of importance in an economic point of view, the flesh of nearly all the Deer-tribe forming an acceptable food for mankind. In our survey of the deer we shall follow as nearly as possible Mr. Lydekker's "Deer of all Lands," the most recent and best authority on the subject. Mr. Lydekker acknowledges eleven genera of this family, containing altogether nearly sixty species. Of these genera ten belong to the typical Deer and one to the Musk-deer (Moschus).

Deer are found in all the six Regions of the world except the Australian and Ethiopian. Their absence in Australia, as is the case with nearly all the highly organized groups of mammals, can be easily understood, but it is difficult to imagine why there should be no Deer in the Ethiopian Region, when in the New World they have passed so abundantly into South America. We are not aware that any explanation can be given of this anomaly, unless it be that their place is taken by the Antelopes. Commencing with the Reindeer (Rangifer) and the Elk (Alces), we find these two types restricted to the northern portions of the Palearctic and Nearctic Regions. Whether it is possible to recognize more than one species of each of these forms is a matter of doubt. At any rate all the local races of both the genera are closely allied.

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 Palearctic 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 Palearctic 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 Palearctic 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 Palearctic Region.

We now come to that strange animal the Milou (Elaphurus) 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 Cervinæ contains the American Deer of which two genera are usually recognized-Cariacus1 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 most 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.

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