3-40 THE TUNDRAS AND STEPPES OP PREHISTORIC EUROPE. 



China, and Japan. All the evidence thus implies for early Pliocene 

 times an equable and uniform climate, which permitted the intimate 

 association in our continent of many plants which are now no longer 

 able to exist at similar elevations or in one and the same latitude. 



The mammalian life of Europe in early Pliocene times was in keeping 

 with the flora. The deinotherium and mastodon still survived, and 

 along with these were rhinoceroses, hippopotamuses, and elephants, 

 and many cervine and bovine animals. Carnivores of extinct and still 

 existing types and many monkeys were also present. 



Such, then, was the character of the climate, and the aspect of the 

 flora and fauna of Europe in preglacial times. The gradual approach 

 of glacial conditions is evidenced by the fact that the percentage of 

 northern and arctic shells in the upper Pliocene marine deposits 

 increases from the lower to the higher members of the series. We note 

 a gradual dying out of southern species and a gradual coming in of 

 northern forms, until at last the beds are charged with the remains of 

 a truly arctic marine fauna. We have no direct evidence as to the 

 terrestrial conditions which obtained in Britain and Ireland at that 

 time. The climate, however, could not have been genial and temperate 

 as it is now. The presence of an arctic fauna in our seas shows that 

 our shores were washed by currents coming from the north, and not as 

 at present from the southwest. Eeasoning from the analogy of to-day, 

 therefore, we might infer that the climate of our area was probably not 

 unlike that of Labrador. 



The traces of the first glacial epoch are more clearly read in the 

 deposits of the continent. An immense glacier at this time, fed from 

 the uplands of Scandinavia, filled the basin of the Baltic. The bottom 

 moraine of that great ice flow is seen in the low grounds of Scania, in 

 southern Sweden, while its fluvio-glacial deposits have been detected 

 at many places in north Germany. The alpine lands were contem- 

 poraneously covered with extensive snow fields, and large glaciers 

 descended the deep mountain valleys, to deploy upon the Vorlander, in 

 Switzerland, and south Germany. The terminal moraines of these 

 glaciers have been mapped out, and the general conditions of the epoch 

 have been so well ascertained that the position of the snow line at the 

 time has been determined. It is believed to have been upon an 

 average some 4,000 feet lower than now. While the valleys of the Alps 

 were thus gorged with ice and the basin of the Baltic was occupied by 

 an immense mer de glace, it is not probable that the higher parts of 

 our islands could have escaped glaciation. We can hardly doubt that 

 snow fields and glaciers must also have existed here. ~No trace of 

 these, however, has been or is ever likely to be detected. Direct 

 evidence of the kind, if it ever did obtain, has been obscured or 

 destroyed by the action of the much greater glaciers and ice flows of 

 later epochs. 



In tracing the succeeding events in the geological history of Europe, 



