192 ZOOLOGICAL GEOGRAPHY. [part hi. 



fact, to these, and the numerous lesser mountains and hills 

 which everywhere diversify the surface of Europe, that the 

 variety and abundance of its animal life is greatly due. They 

 afford the perennial supplies to rivers, and furnish in their 

 valleys and ever varying slopes, stations suited to every form 

 of existence. A considerable area of Central Europe is oc- 

 cupied by uplands of moderate elevation, a comparatively 

 small portion being flat and marshy plains. 



Most of the northern and much of the central portions of 

 Europe are covered with vast forests of coniferous trees ; and 

 these, occupying as they do those tracts where the winter is 

 most severe, supply food and shelter to many animals who could 

 not otherwise maintain their existence. It is probable that 

 the original condition of the greater part, if not the whole, of 

 temperate Europe, except the flat marshes of the river valleys 

 and the sandy downs of the coast, was that of woodland and 

 forest, mostly of deciduous trees, but with a plentiful admixture 

 of such hardy evergreens as holly, ivy, privet, and yew. A 

 sufficient proportion of these primeval woods, and of artificial 

 plantations which have replaced them, fortunately remain, to 

 preserve for us most of the interesting forms of life, which 

 were developed before man had so greatly modified the surface 

 of the earth, and so nearly exterminated many of its original 

 tenants. Almost exactly in proportion to the amount of 

 woodland that still remains in any part of Europe, do we 

 find (other things being equal) the abundance and variety 

 of wild animals; a pretty clear indication that the original 

 condition of the country was essentially that of a forest, a 

 condition which only now exists in the thinly inhabited regions 

 of the north. 



Although the sub-region we are considering is, for its extent 

 and latitude, richly peopled with animal life, the number of 

 genera altogether peculiar to it is not great. There are, however, 

 several which are very characteristic, and many species, both 

 of the smaller mammalia and of birds, are wholly restricted 

 to it. 



Mammalia. — The genera wholly confined to this sub-region are 



