348 THE HOLARCTIC REGION. [CHAP. 



During the Plistocene the region within the Arctic circle en- 

 joyed a decidedly less rigorous climate than it at present pos- 

 sesses. In Baron von Toll's recent expedition to the New Siberian 

 Islands 1 , where, as previously stated, remains of the tiger have been 

 obtained, it was discovered " that under the perpetual ice, in a 

 freshwater deposit, which contained pieces of willow and bones of 

 post-tertiary mammals (the mammoth-layer) were complete trees 

 of Alnus fruticosa, fifteen feet long, with leaves and fruit. It was 

 thus evident that during the mammoth-period tree-vegetation 

 reached the seventy-fourth degree of latitude, and that its northern 

 limit was at least three degrees further north than it is now." 



The next sub-region is the European, which may be taken to 

 include all that part of Europe lying between the 

 Arctic sub-region in the north, and the line of the 

 Pyrenees and Alps, continuing eastwards along the 

 northern shore of the Black Sea to the Caucasus and the Caspian 

 Steppes. This area includes the typical fauna of the eastern 

 Holarctic region, among its more or less characteristic mammals 

 being (in the north) the elk also ranging into America , the red 

 deer (unknown in America, but represented by a variety in North 

 Africa), the roe, the bison, the chamois, the Alpine ibex, the 

 typical variety of the brown bear, the badger, the wolverene (in the 

 north), the Alpine marmot (Arctomys marmotta), the dormouse, 

 hamster, mole, and hedgehog \ several of these being, however, 

 common to the Arctic and Central Asian sub-regions. The des- 

 mans (Myogale) are restricted to this sub-region ; and the same 

 was probably the case with the aurochs (Bos taurus, var. primi- 

 genius], the ancestral stock of our domestic cattle. Finally, the 

 Caucasus is the home of two or three peculiar species of goats 

 (Capra cylindricornis and C. caucasica] known as ture. 



It will be unnecessary, even if this could be accomplished, to 

 give a complete list of the mammalian fauna of this sub-region, 

 but it is essential to refer to the comparative poverty of the fauna 

 of the British Islands as compared with that of the Continent. 

 The following list includes all the mammals (exclusive of bats) 

 known to have inhabited the British Islands within the historic 



1 See Knowledge, 1895, p. 106. 



