Carthaillac places the whole palanthropic age as quaternary, properly so-called, which he separates from the tertiary on the one hand and the modern on the other, and divides his quaternary into two stages, the first characterised by _E. antiquus_ and Mortillet's Chellean men, the second by the mammoth and reindeer--the earlier of these two periods being warm and moist, the latter cold and dry. The table appended to this chapter is modified from those of Carthaillac. Dawkins, while admitting a similar twofold division, calls the earlier men those of the river gravels, the latter those of the caves. This twofold division of the palanthropic age requires some consideration. In the first place, there is reason to believe that the Canstadt race locally preceded that of Cro-magnon. I say locally, for no one supposes that they are distinct species, and as varietal forms they may have originated from a common intermediate ancestor, or the humbler race may be the earlier, and the higher race an improvement on it, or the lower race may have been a degraded type of the higher. Probably also there was a third, the Truchère race, and the Cro-magnon race may have been a half-breed or metis progeny. [Illustration: TOOTH OF CAVE BEAR, WITH ENGRAVING OF A SEAL, FROM A COLLAR FOUND AT SORDES, PYRENEES (after Carthaillac)] Again, there was an undoubted change of fauna within the palanthropic age, and this dependent on or accompanied by a change of climate. The earlier elephant of the period (_E. antiquus_) and its companion animals are believed to have been suited to a warm climate, and to have entered Europe from the south-*east. With, or immediately after, them came man, and this conclusion harmonises with human physiology, for we know that man must have originated in a warm climate, and must in the first place have been a feeder on fruits and grains or other nutritious vegetable products. In this early stage he would be nearly destitute of implements and weapons. But in the succeeding cold period, one tribe after another might be obliged to resort to hunting habits, to the use of fire and of clothing, and of natural and artificial shelter. Hence the peculiarities of the cave men, who, while they advanced in art, may have also advanced in ferocity and warlike habits, under the pressure of necessity and competition. Hence also their association more and more closely with such animals as the reindeer, the hairy mammoth, and the woolly rhinoceros, while the previous species had migrated to the south or perished. Thus it would appear that the men of the mammoth age may not be really the most primitive men, but a derivative from them under pressure of a severe climate. This possibility may be summed up as follows. If the early part of the post-glacial or palanthropic era was characterised by a milder climate than its later period, this may have had much to do with the change in implements and weapons. The earliest