Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 18. (Budapest 1921)
Éhik, Gy.: The glacial-theories in the light of biological investigation
10-4 Dr. J. ÉHIK zone, whilst Ihe exclusively thermophil steppe elements continued to inhabit Ihe warm plains. The problem is somewhat complicated by the fact of some forestal species being included in the postglacial steppe fauna. There is no reason however to look for a complicated solution of the question ; if sylvicol elements are simultaneously occurring with those belonging to another type, this proves only, with an absolute certainty, that forests existed of yore on the respective spot. I share throughout Mr. LIEBE'S opinion, according to which the mountains of Bohemia and Moravia were covered with woods at the end of the diluvial period, as well as the Alps, thus constituting the centres from which the large forests took later 011 their extension. 1 1 see no reason to contest this supposition, the appearance of forests having occurred, after the regression of the ice, in mountainous regions. Thus in the postglacial period sylvicol elements might have already existed.Taking all the preceeding facts into consideration, it might be established that two important faunistical evolutions are due to the glacial period. The first result was produced by the extending of ice, removing the tropical fauna in a southern direction, as far as Africa, confining its presence to a territory being until that period so to say thoroughly uninhabited. The conditions met with on this territory gave raise to an enormous development of the new settlers, multiplying the number of their species. The second evolution is a consequence of the withdrawing ice. Immense territories, uninhabited during their glaciation, were liberated, offering a new scene for the struggle for life. They were hardly populated by the psychrophil species as the development resp. the différenciation of the steppe and sylvicol fauna began. By the formation of the steppe the Lemmings were removed to more northern latitudes, whilst the steppe itself was gradually restricted by the increase of the forest zones, and finally confined to the territory of the present Russian steppes. The definitive development of the forest zones, separating the steppe and tundra, falls already in the Holocene period. 1 LIEBK, Die fossile Fauna der Höhle Vypustek in Mähren etc. Sitz. Ber. d. k. Akademie, Wien, 1879. Bd. 79. I. Abt. p. 488. * Baron F. NOPCSA, with whom I had the pleasure te talk about this question, observed that sylvicol elements must have existed even at an earlier date; the absence of old Pliocene sylvicol remains may be attributed to the fact of forests being, in general, a rather unfit territory for fossilisation. Such an ancient sylvicol fauna was found by me in the Fortyogó („Gespreng") hill near Brassó. (See: ÉHIK , Die präglaziale Fauna von Brassó, Földtani Közlöny XLllI. 1913.)
