The same sharp line of demarcation exists between the two faunas on the continent. The panther, _Felis Caffer_, lynx, spotted hyæna, musk-sheep, hippopotamus, and the extinct group disappeared. The African elephant forsook Spain and Sicily, the striped hyæna the south of France, before the prehistoric period; while the _Elephas meridionalis_ and pigmy hippopotamus of Sicily, and the pigmy elephant and gigantic dormouse of Malta, became extinct. Speaking in general terms, the wild fauna of Europe, as we have it now, dates from the beginning of the prehistoric age, and consists merely of those animals which were able to survive the changes by which their pleistocene congeners were banished or destroyed. The arrival of the domestic animals under the care of man in the neolithic age, and their extension over the whole of Europe in a wild or semi-wild state, coupled with the disappearance of the wild species mentioned above, constitutes a change in the mammal life at least as important as any of those which define the meiocene from the pleiocene, or the pleiocene from the pleistocene periods. _Physical changes--The excavation and filling up of Valleys._ The magnitude of the interval between the two periods may also be gathered from the great changes which have taken place in physical geography. In nearly every valley in Great Britain, certain areas to be mentioned presently excepted, are strata of sand and gravel, proved to be of pleistocene age by their fossil mammals, and by their fluviatile shells to have been deposited by rivers. They occur at various heights, forming sometimes terraces, and at others isolated patches, which were accumulated when the river flowed at their level, and before the valleys were cut down to their present depth. Those at Fisherton near Salisbury, described by Sir Charles Lyell, Mr. Prestwich, Mr. John Evans,[175] and others, may be taken as an example. [Illustration: FIG. 74.--Section of Valley-gravels at Fisherton. (Evans.)] The valley through which the river Wily flows is excavated in the chalk (Fig. 74), and on its northern side fluviatile deposits occur at two levels, represented in the accompanying section. One patch of gravel, about twelve feet thick, _a_, lies about eighty feet above the present level of the Wily; while a second, _b_, consisting of clayey brickearth or loam, with seams of gravel, and fluviatile shells, sweeps down from a lower point to the bottom of the valley, and passes under the river. From the deposit _a_, Dr. Blackmore obtained many rudely-chipped implements, of the same palæolithic type as those found with the extinct mammalia in the gravel beds at Amiens and Abbeville in the valley of the Somme. In the deposit _b_, fossil mammalia were met with belonging to the following animals:-- Spotted hyæna. Lion. Reindeer. Stag. Bison. Urus. Musk-sheep. Wild boar. Horse. Woolly rhinoceros. Mammoth. Lemming. Pouched marmot. Hare.