The cold, dry period, when the full tide of steppe life reached western Europe, is of somewhat uncertain date; it probably began during the stage of the middle Magdalenian industry and continued into the late or high Magdalenian. There was certainly an environment attractive to these peculiar and very highly specialized mammals, which at the present time are neutral in color, swift of foot, inured to existence on very sparse vegetation, and adapted to extremes of heat and cold. Among the smaller steppe forms were the suslik or pouched marmot of the steppes (_Spermophilus rufescens_) and the steppe hamster (_Cricetus phæus_), also the Siberian vole (_Arvicola gregalis_); still more characteristic was the great jerboa (_Alactaga jaculus_), with long, springy hind legs, and the saiga antelope (_Antilope saiga_). With these mammals appeared the steppe grouse (_Perdix cinerea_), which is found along the Danube in late Magdalenian strata; another bird characteristic of the northern steppes and tundras is the 'woodcock owl' (_Brachyotus palustris_). Accompanying these mammals was undoubtedly the steppe horse (_Equus przewalski_), now restricted to the desert of Gobi; it is said to occur in the grottos of northern Switzerland. It would appear that the saiga antelope may have reached eastern Europe in late Solutrean times, for its outline is said to be found in an engraving at Solutré. Widely spread over Europe was the giant Elasmothere; it would seem very unlikely that this animal was present in Magdalenian times, for it certainly would have attracted the attention of the artists. Neither have we any positive artistic records of the wild ass, or kiang, although certain of the drawings in the grottos of Niaux and Marsoulas, of the middle Magdalenian, also of Albarracin, in Spain, may be interpreted as representing this animal. Thus the Asiatic steppe and desert fauna, which in the region of the upper Rhine and Danube was restricted to two species of mammals in Aurignacian and Solutrean times, rises to nine or ten species in middle Magdalenian times, so that for the first time during the entire 'Reindeer Epoch' the steppe and tundra faunæ are equally balanced. There are also six or seven species of birds from the moors and uplands of central Asia. The bird life depicted in middle Magdalenian art includes the ptarmigan or grouse, the wild swan, geese, and ducks.