1907. Moffat. — The Problems of an Island Fauna. 135 



the reality of this Siberian invasion of the region left bare of 

 life by the drying of the Mid-European Sea — the sea that in 

 Glacial times seems to have covered most of Russia, Germany, 

 Denmark, South Sweden, and the Netherlands. On the re- 

 treat of that sea, of course, the new plain would also be invaded 

 by the old European fauna that had lived on its western shore ; 

 but it would not at once be so full) 7 occupied by these creatures 

 as to form part, as it were, of their old ancestral domain ; and 

 thus there would be for a time a real. new highway across 

 Europe without pre-supposing any inferiority on the part of 

 the old West-Eurasian animals to oblige those creatures to 

 give place to — or to die out before — the Eastern invaders. 

 There would be in Germany a grand commingling of East 

 and West, a fresh scramble, from which almost anything might 

 emerge. Still, if many of the new Siberians ultimately sur- 

 vived, it must, one would think, have been at the cost of some 

 of their Western competitors. This brings us back to the 

 •question — Do the Irish fauna and flora of to-day, with their 

 extreme deficiency in number of species, represent to our eyes 

 what the fauna and flora of Western Europe were like before 

 the breaking out of this conflict with the Army of the East, 

 and up to the time when Ireland saw herself finally cut adrift ? 

 If so, how can we account for such extreme poverty in a con- 

 tinental area ? And if not, how can we explain the losses that 

 our own fauna and flora must have suffered since the days 

 when we became an island ? 



A little time ago, we all possessed a very satisfactory answer — 

 or what seemed to be so — to questions of that kind. There 

 was that terrible phenomenon the Great Ice Age. That, surely, 

 was sufficient — if we could believe half the accounts that men 

 of science gave us of its dismal character — to explain any con- 

 ceivable amount of extermination. If Ireland was cut off be- 

 fore the Britannic area had had full time to recover from the 

 effects of the Ice Age, that would amply explain why her 

 fauna continued poor; and, of course; if we were insulated at 

 a yet earlier date, before the maximum severity of the Glacial 

 Age had been reached, the explanation would then be so per- 

 fect that the difficulty would present itself in an opposite form — 

 How did any of our plants and animals survive ? But our 

 leading zoologists have of late given so much attention to the 



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