THE PEOPLING OF THE EARTH.-Dr. Aleš Hrdiička in No. 3, vol. 55, of the Proceedings of the American Philosophical Society, reviews conclusions on the place of origin and distribution of man put forward in 1921 in the light of the evidence collected by him in his recent journey through parts of Europe and Asia, Australia, and South Africa. On the question of the origin and cradle of mankind, he holds to the view that this must be sought in western and south-western Europe, with probably an early extension of the species, on one hand towards central Europe, and on the other, over the watershed of the Mediterranean. It is probable that by the time the last or Wiirmian glaciation was approaching, man existed in only one general form-the Neanderthal, which persisted for a very long time into post-glacial times. The view that Neanderthal is a separate species which completely died out is erroneous. It is a necessary stage of man's evolution, and if Homo sapiens is given another place of origin, say Asia, a Neanderthal phase must be postulated there. Probably be became much reduced in numbers in western Europe and his place was taken by transitional Aurignacian man who was nearing the modern type, having developed from an extension of the Neanderthal eastwards beyond central Europe, which afterwards returned westwards as Aurignacian man to the place of his Neanderthal forefathers. After the last glacial period there is a rapid extension of culture, and man for the first time in his history becomes capable of furnishing a surplus of numbers needing an extension of his domain. It was during this time that the foundation was laid for man's differentiation into the older human stocks and races. Apart from the corroboration of the above views, three, or rather four, conclusions emerge as a result of Dr. Hrdlicka's journey. A link between the Negritos of Africa and of south-eastern Asia has been found in India; it is clear that the Australian (and Tasmanian) is one of the more fundamental races of the world with close connexion with our own ancestral stock; there are in Asia remnants of the old yellowbrown stock from which is derived the American Indian, e.g. the Tibetans; and lastly, in Australia and South Africa new types of white man are developing.