X. During all the first part of the reindeer age, the Cro-Magnon race supported itself in the state, of which I have just been pointing out the principal features. But from the commencement of the second half of the same age, during the deposition of the red diluvium and the upper loess, we observe an unmistakable decline, which becomes more and more striking as we proceed. The working of bone and reindeer antlers diminishes and returns to its former rudeness; flint cutting, on the contrary, gains in favour, and in some places, as in the grotto discovered at Saint Martin d’Excideuil by M. Parrot, acquires a most remarkable finish. But this very perfection seems to herald the approach of a new age, and to betray the influence of a strange element. The fact is, that during this period an amelioration in the general conditions of life was taking place. Europe had at length risen above the waves; a continental climate was succeeding to the maritime climate: the weather was more settled; warm summers followed winters more severe, but less rainy; the glaciers consequently retreated and became confined within their present limits; and consequently again, the fauna became divided. Animals fond of cold, and organised for a mountain life, such as the chamois and bouquetin, were content to emigrate _in altitude_, and followed the glaciers in their retreat to our highest mountain summits. The reindeer, in no way adapted for climbing, was forced to emigrate _in latitude_ and go further north. Its herds became more and more rare, and at length disappeared from our countries, where, even if domesticated, it could not have continued for long. The human population, who had, doubtless, for centuries lived upon this animal, and obtained from it their clothing, arms, and implements, must have felt the change intensely, losing with the reindeer, what we may call their staff of life. What happened now? According to MM. Cartailhac, Forel, and de Mortillet, man disappeared or emigrated with the animal which had become necessary to him, and the valleys of Périgord, Mâconnais, and the Pyrenees became uninhabited. They hold that, after the close of the reindeer age, there is an immense space, a great gap, during which the fauna was renewed, and after which a new race of men suddenly made their appearance, who polished stone instead of cutting it, and surrounded themselves with domestic animals.