When the Editor of ANTIQUITY approached the authors and suggested that some of his readers would welcome a visual table showing the occurrence and sequence of the different prehistoric cultures, the matter did not seem to be one of outstanding difficulty. When the time came, however, to produce the work, it was found to be quite otherwise. Perhaps the ideal method would have been to prepare a series of gigantic distribution maps of the area to be covered (Europe, the Mediterranean Basin and adjacent regions) during the different prehistoric periods. But the preparation and publication of such maps on a scale large enough to be at all helpful would have presented insuperable difficulties. The more diagrammatic method which has been adopted divides up the map into several geographical areas which will be found heading the various columns of the table. These areas have been chosen and arranged as conveniently as possible in the light of the general distribution of the early and later prehistoric cultures.

It must always be remembered, however, that the spread of a culture from its area of origin corresponds to the ever-widening rings formed by a stone which is cast into a pond—its influence lessens as we get farther from the centre of diffusion. It is not easy to represent this lessening influence diagrammatically. Of course when the industries of a culture have spread widely over a neighbouring area, its name appears in the appropriate column of the table. Where, however, they are only very rarely found, perhaps as the last, faintest ripple of the circles, or where, as with the Solutrean culture in Spain south of the Pyrenees, they are only present in a small corner of the area adjacent to another thickly sprinkled area (France) whence they have clearly percolated, it would have presented an erroneous picture to have cited the culture-name.