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Dr. J. ÉHIK 
zone, whilst the exclusively thermophil steppe elements continued to 
inhabit the warm plains. 
The problem is somewhat complicated by the fact of some foresta! 
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 weil as the Alps, thus constituting 
the centres from which the large forests took later on their extension. 1 
I 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. 2 
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 Liebe, Die fossile Fauna der Höhle Vypustek in Mähren etc. Sitz. Ber. d. k. 
Akademie, Wien, 1879. Bd. 79. I. Abt. p. 488. 
2 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 XLIIl. 1913.). 
