If we were writing upon the general subject of the antiquity and development of the human race, we should speak here in detail of several other caves and rock shelters in France and southern Europe, where remains of man belonging to an earlier period have been found. We should mention the rock shelter of Cro-Magnon in the valley of Vezère, as well as that of Mentone, where entire human skeletons were found. But it is doubtful if these and other remains from caves which might be mentioned belong in any proper sense to the Glacial period. The same remarks should be made also with reference to the lake-dwellings in Switzerland, of which so much has been written in late years. All these belong to a much later age than the river-drift man of whom we are speaking, and of whom we have such abundant evidence both in Europe and in America. [Illustration: Fig. 82.--Tooth of Machairodus neogæus, × 1/6 (drawn from a cast).] [Illustration: Fig. 83.--Perfect tooth of an Elephas, found in Stanislaus County, California, 1/8 natural size.] _Extinct Animals associated with Man during the Glacial Period._ This is the proper place in which to speak more fully of the extinct animals which accompanied man in his earliest occupation of Europe and America, and whose remains are so abundant in the river-drift gravel and in the caves of England, in connection with the relics of man. Among these animals are The Lion, which is now confined, to Africa and the warmer portions of Asia. But in glacial times a large species of this genus ranged over Europe from Sicily to central England. The saber-toothed Tiger, with tusks ten inches long: (Machairodus latidens), is now extinct. This species was in existence during the latter part of the Tertiary period, but continued on until after man's appearance in the Glacial period. The presence of this animal would seem to indicate a warm climate. The Leopard (_Felis pardus_) is now confined to Africa and southern Asia, and the larger islands adjoining; but during man's occupation of Europe in the Glacial epoch he was evidently haunted at every step by this animal; for his bones are found as far north in England as palæolithic man is known to have ranged. The Hyena. Two species of this animal are found in the bone-caves of Europe. During the Glacial epoch they ranged as far up as northern England, but they are now limited to Africa and southwestern Asia. [Illustration: Fig. 84.--Skull of _Hyena spelæa_, × 1/4.]