At some date of unknown remoteness--it may be a hundred or two hundred thousand years ago--a primitive type of man entered the island continent of Australia, coming from New Guinea and the islands of the Malay Archipelago. The period in human history was perhaps so distant from our days that the geographical conditions of the Malay Archipelago were not precisely what they are at the present day; islands now separated by shallow seas may have been joined one to the other, the southern projections of New Guinea and the northern peninsulas of Australia may have been much closer together, so that men, though living a life of absolute savagery representing the lowest grade of human intelligence, were nevertheless able, by making use of floating logs or roughly fashioned rafts,[10] to enter the Australian continent and to pass from New Guinea eastwards and southwards into the nearer archipelagos of the Pacific. Although, doubtless, changes have taken place during the last hundred thousand years in regard to the distribution of land and water between south-eastern Asia and Australia, and even over the surface of the Pacific Ocean; and although islands or islets may have since subsided that once served as stepping-stones for adventurous savages: nevertheless there cannot have been within this period of time--which is scarcely a second in the age of the planet on which we dwell--the rise of any continuous land surface between the continent of Asia and the great Malay islands, on the one hand; and New Guinea, Australia, New Caledonia, the New Hebrides, and Fiji, on the other. Because if there had been any such continuous land connection within the last two hundred thousand years, sufficient to effect the peopling of Australasia by the human species without the need of crossing straits and narrow seas, there would have come into these regions as well as Man many examples of the modern animals of Asia. But, as we know, the south-eastern part of the Malay Archipelago and all Australasia and the Pacific islands are singularly deficient in the types of mammal now existing in Asia. In New Guinea, Australia, and the Malay islands to the east of Celebes and Bali, there are no monkeys, cats, wild oxen, or deer (excepting in the Moluccas and Timor), no apes, bears, insectivores, squirrels, elephants, rhinoceroses, or tapirs. Elephants, tapirs, apes, tigers, and rhinoceroses got as far east as Java (though the two first are now extinct there), and if there had been continuous land connection from that region eastwards to New Guinea and Australia, which made human emigration thither possible without crossing the sea, then these other large mammals would have equally invaded Papuasia and Australia. That they did not penetrate farther east than Java shows that a broad sea strait must have intervened, and the fact that this strait--or rather a succession of straits---did not prevent the Tasmanians, the Negroes of New Guinea and the Bismarck Archipelago,