A great modification in the fauna corresponds to the deposition of the _mean upper alluvium_ (_moyens niveaux supérieurs_). The great carnivora and the mammoth become more and more rare, till at length they disappear altogether; the horse no longer predominates; the reindeer has taken its place, and wanders in vast herds over lands which are gradually subsiding. Man has profited by these changes. New races, perfectly distinct from the preceding ones, appear upon our soil. That of the preceding age develops and attains a certain degree of civilization, attested by true works of art. At length, the bottom of the ocean rises, and Europe is complete. The polar ice is confined within its present limits, and the insular climate gives place to a continental one, with its extremes of heat and cold. The glaciers of our mountains gradually contract, and withdraw to higher regions. The animal species, no longer finding in the same latitude the temperature suitable to them, emigrate, some to the south, others to the north, or to the higher mountains. Man must necessarily have felt the consequence of these changes. When the animals which formed the basis of his nourishment disappeared, never to return, a part at least of the population must have followed, and emigrated at the same time. The rising societies were thus shaken to their very foundations, and whilst some tribes went off in opposite directions, those which remained behind, experienced a decline of which we may observe the traces in the works which they have bequeathed to us. They were but too easily absorbed by superior races, who brought domestic animals with them, and substituted the pastoral life for that of the hunter. III. The man of the quaternary period has left here and there a few of his bones by the side of those animals who were his contemporaries. The human bones in question belong, however, almost exclusively to Europe. The fossil man of other parts of the world is almost unknown to us. Lund is said to have discovered it in certain caves in Brazil. But unfortunately we have no other details of this discovery than a short note and two drawings of small dimensions, published quite recently by MM. Lacerta and R. Peixoto. Much has been said about the skull discovered by Whitney in California. Unfortunately, the description of this specimen has not appeared, so that doubts have, on several occasions, been expressed as to the existence of the fossil itself. The recent testimony of M. Pinart has removed them, but has, at the same time, created the most serious doubts as to the antiquity of this specimen, which seems to have been found in disturbed grounds.