Asia is rich in variety of animal life, and especially so as regards the class mammalia, all the orders of which but two (the marsupials and the edentata) are represented in its zoology. Of domesticated quadrupeds, the camel, ox, goat, and sheep, among the ruminants, with the horse, the ass, and the elephant, among pachyderms, are natives of Asia. The camel, of which there are several species, all natives of this continent, ranges from the shores of the Indian Ocean and Red Sea as far north as Lake Baikal. The reindeer and elk frequent the Siberian and Mongolian plains, migrating from the former locality southward with the approach of winter. Numerous varieties of the ox tribe (including the common ox, aurochs, buffalo, and yak) are reared by the Tartar nations who inhabit the upland plains of the interior. The antelope and deer tribe, of which there are a vast number of species, belong to the western and southwestern regions of the continent. The plains of Turkestan, to the eastward of the Caspian, are perhaps the original country of the horse. The wild ass is indigenous to Western Asia. The elephant is not found to the west of India, nor to the north of the Himalaya Mountains; it belongs only to the two Indian peninsulas, with Ceylon, and some of the smaller islands of the Malay archipelago. Among Asiatic carnivora are the lion, tiger, leopard, panther, and ounce, of the cat genus: the wolf, hyena, and jackal, of the dog tribe. Two species of bear are native to the Himalaya region (the snow-bear, and the black-bear) and the polar bear belongs to the Arctic coasts of the continent. The lion of Asia is now restricted to the region which extends from the banks of the Euphrates and Tigris to the western coasts of the Indian peninsula, including the deserts of Mesopotamia, Persia, and Hindostan. The tiger has a more extensive range, and inhabits all the middle and southeastern divisions of the continent. The hyena, and also the jackal, belong to the western half of Southern Asia; the wolf frequents the northern and western plains, and is found in a range of country extending from Siberia, through Turkestan, to the shores of the Mediterranean. The dog and the fox are common all over the continent, and present numerous varieties; in Kamtchatka and some parts of Siberia, the former animal is used as a beast of burden, and is trained to draw the sledges over the vast plains of ice and snow.