THE LENGTH OF POSTGLACIAL TIME AND THE ANTIQUITY OF THE AURIGNACIAN CULTURE
The most recent discussion on the length of Postglacial time was that held at the Twelfth International Congress of Geology, in Ottawa, in 1913 (Congrès Géologique International, Compte-rendu de la XII Session, Canada, 1913, pp. 426-537). The notes abstracted by Dr. Chester A. Reeds from the various papers are as follows:
"American estimates of Postglacial time have been made chiefly from the recession of waterfalls since the final retreat of the great ice-fields in North America. The retreat of the Falls of St. Anthony, Minnesota, has been estimated by Winchell at 8,000 years and by Sardeson at 30,000 years. The retreat of the Falls of Niagara has been estimated as requiring from 7,000 to 40,000 years; it has proved a very uncertain chronometer, because of the great variation in the volume of water at different stages in its history. The recession of Scarboro Heights and other changes due to wave action on Lake Ontario have been estimated by Coleman as requiring from 24,000 to 27,000 years. Fairchild has estimated that 30,000 years have elapsed since the ice left the Lake Ontario region of New York.
"In Europe the most accurate chronology is that of Baron de Geer on the terminal moraines and related marine clays of northern Sweden. For the retreat of the ice northward over a distance of 370 miles in Sweden 5,000 years were allowed; for the time since the disappearance of the ice in Sweden, 7,000 years; for the retreat of the ice from Germany across the Baltic, 12,000 years; giving a total of 24,000 years as compared with a total of between 30,000 and 50,000 years allowed by Penck for the retreat of the ice-fields of the Alps."
NOTE VII
THE MOST RECENT DISCOVERIES OF ANTHROPOID APES AND SUPPOSED ANCESTORS OF MAN IN INDIA
It is possible that within the next decade one or more of the Tertiary ancestors of man may be discovered in northern India among the foot-hills known as the Siwaliks. Such discoveries have been heralded, but none have thus far been actually made. Yet Asia will probably prove to be the centre of the human race. We have now discovered in southern Asia primitive representatives or relatives of the four existing types of anthropoid apes, namely, the gibbon, the orang, the chimpanzee, and the gorilla, and since the extinct Indian apes are related to those of Africa and of Europe, it appears probable that southern Asia is near the centre of the evolution of the higher primates and that we may look there for the ancestors not only of prehuman stages like the Trinil race but of the higher and truly human types.
As early as 1886 several kinds of extinct Old World primates, including two anthropoid apes related to the orang and to the chimpanzee, were reported from the Siwalik hills in northern India, and recently Dr. Pilgrim, of the Geological Survey, has described three new species of Siwalik apes resembling Dryopithecus of the Upper Miocene of Europe, also an anthropoid which he has named Sivapithecus and regards as actually related to the direct ancestors of man, a conclusion which may or may not prove to be correct. Another extinct Indian ape, Palæopithecus, is of very generalized type and is related to all the anthropoid apes.
NOTE VIII