120 HISTORY OF THE EUROPEAN FAUNA. 



Germany the remains of the same mammals occur in 

 deposits which are certainly more recent than the 

 lower continental boulder clay; and he is inclined to 

 the belief that they migrated into Europe during the 

 inter-glacial phase which is supposed to have separated 

 the earlier from the later stage of the Glacial period. 

 It is evident that in this case the inter-glacial period 

 in Germany would have corresponded to, and be con- 

 temporaneous with, our Forest-Bed period. The 

 deposits immediately preceding the Forest-Bed would 

 also be contemporaneous with the lower continental 

 boulder clay. Although this may seem rather a 

 startling statement to make, from the evidence 

 which will be brought forward in the fourth and 

 fifth chapters I am inclined to the belief that such 

 is probably the case. 



Having once arrived at a determination of the 

 exact geological period during which the Siberian 

 mammals invaded our continent, and having also 

 previously determined the relative ages of the various 

 other migrations, we have advanced another step in 

 the direction we are aiming at Let us suppose that 

 the Siberian migration actually reached the British 

 Islands during the Forest-Bed period. Since the 

 Siberian migration is the most recent of those which 

 entered the British Islands, the others must have 

 commenced their march before the Forest-Bed 

 period. Now it was Professor Boyd Dawkins who 

 first indicated to us, as I have remarked before, 

 the method of research to be adopted in an attempt 



