The opening of I. GENERAL CONSIDERATIONS
The World peopled by Migration from one Centre by Pleistocene Man--The Primary Groups evolved each in its special Habitat-- Pleistocene Man: Pithecanthropus erectus; The Mauer jaw, Homo Heidelbergensis; The Piltdown skull, Eoanthropus Dawsoni--General View of Pleistocene Man--The first Migrations--Early Man and his Works--Classification of Human Types: H. primigenius, Neandertal or Mousterian Man; H. recens, Galley Hill or Aurignacian Man-- Physical Types--Human Culture: Reutelian, Mafflian, Mesvinian, Strepyan, Chellean, Acheulean, Mousterian, Aurignacian, Solutrian, Magdalenian, Azilian--Chronology--The early History of Man a Geological Problem--The Human Varieties the Outcome of their several Environments--Correspondence of Geographical with Racial and Cultural Zones.
In order to a clear understanding of the many difficult questions connected with the natural history of the human family, two cardinal points have to be steadily borne in mind--the specific unity of all existing varieties, and the dispersal of their generalised precursors over the whole world in pleistocene times. As both points have elsewhere been dealt with by me somewhat fully[1], it will here suffice to show their direct bearing on the general evolution of the human species from that remote epoch to the present day.