Another striking proof of the amelioration of climate is the return of the flint workers to many of the open stations, old and new, in various parts of western Europe, the climate being more endurable because less humid. In Mousterian times the open stations were very rare and were perhaps visited during the summer season only; in Aurignacian times they were more abundant, there being twelve open stations out of a total of about sixty stations thus far discovered; in Aurignacian and Solutrean times the type station of Solutré was much frequented, and many other open camps are found in various parts of western Europe. This is still the Reindeer Period; in fact, it is the typical 'Reindeer Epoch' of Lartet, and the predominant forms of life are the woolly mammoth and the woolly rhinoceros; but for a time the reindeer seems to have been less abundant, and Aurignacian times are marked apparently by a very greatly increased number of horses. The animal life throughout retains its northern or arctic character; the tundra species predominate, the hardy forms of the forests and meadows of Eurasia are next in number, and then are found a few of the steppe forms, with here and there forms characteristic of the Alps. The entire fauna of the Aurignacian may be summed up as follows: The wild ass, or kiang, of the Asiatic deserts appears in late Aurignacian times in the region of the upper Rhine and upper Danube, as seen in the deposits of Wildscheuer, Thaingen, Kesslerloch, and Schweizersbild, and also there probably arrived in Europe at this time the Elasmothere (_E. sibericum_), a gigantic rhinoceros, distinguished from all others that we have been considering by the entire absence of the anterior horn and by the possession of an enormous single horn situated on the forehead above the eyes, also by the elaborate foldings of the dental enamel, to which the name 'Elasmothere' refers; its teeth were especially adapted to a grassy diet; it apparently wandered into Europe from the arid grassy plains of central and western Asia, and its appearance is connected with the extensive deforestation accompanying the tundra and steppe periods of mammalian life. TUNDRA LIFE. Reindeer, woolly mammoth, woolly rhinoceros, musk-ox (rare), arctic fox, arctic hare, arctic wolverene, arctic ptarmigan. Banded and Obi lemmings in lower Aurignacian only. ALPINE LIFE. Argali sheep, ibex, alpine ptarmigan. STEPPE LIFE. Steppe horse, kiang, central Asiatic ass. FOREST LIFE. Red deer, roe-deer, giant deer, brown bear, cave-bear, wildcat, wolf, fox, otter, lynx, weasel. MEADOW LIFE. Bison, wild cattle. ASIATIC LIFE. Cave-hyæna, cave-lion, ? cave-leopard. These periodic arrivals from central Asia suggest the existence of migration routes which may also have been followed by tribes of Palæolithic hunters.