ScHARFF — On the Origin of the European Fauna. 505 



"We hare geological proofs that the Siberian fauna migrated to p. 46& 

 Europe on a tract of country, known as the " Tchemosjem " or black 

 earth, of Russia, and that this originated from the decay of grass which 

 grew there during long ages. This fauna then invaded Central 

 Europe and Great Britain, In Prance its further progress was 

 arrested by the Eiver Garonne. England and Erance must there- 

 fore have been connected ; whilst the absence of deposits contain- 

 ing Siberian Mammals from Scandinavia proved that it was sepa- 

 rated from the Continent. 



The jS'orthern or Arctic element in the Irish fauna must have p. 469 

 come directly from the north. It is more or less confined to the 

 northern and western parts of Ireland, and forms a large proportion of 

 the fauna of Scotland and Scandinavia. It suggests that a land- 

 connexion between the latter and the British Islands must have existed. 

 The present and past range of the Arctic hare, the reindeer, and the 

 stoat are discussed in detail to show that such a connexion actually 

 united the two countries. Eeference is also made to the Korth Ameri- 

 can species occurring in Ireland which belong to the same migra- 

 tion. 



The evidences in favour of a former land-connexion between Scandi- p. 479 

 navia and Greenland via Spitsbergen are now reviewed. 



It is suggested that the American Marine Mollusca which have p. 479 

 been discovered in late Tertiary deposits of the east coast of England 

 reached that coast, not from the Atlantic, but from the Arctic Ocean 

 by means of the sea which extended from the White Sea to the 

 German Ocean. 



The migration of terrestrial animals and plants from this ancient P- 479 

 northern land southward took place chiefly during tlie deposition of 

 the newer English crags, and of the Continental lower boulder-clay, 

 that is to say, before the Siberian migrants set foot on British soil. 



The southern migration to the British Islands commenced earlier P- 479 

 than either the Arctic or the Siberian. jS'umerous instances are quoted 

 to prove that the southern fauna is composed of species of south- 

 western and of southern and Central European as well as of Asiatic 

 origin. 



In connexion with the origin of the Eed Deer, the nature of the p. 479 

 geographical changes which the Mediterranean basin has undergone 

 during later Tertiary times are now discussed. 



In the next pages I have endeavoured to show that Ireland wasp. 483 

 separated from England at the time while the migration from Southern 

 and Central Europe was in progress. The contradictory evidence from 



