NORTH EUROPEAN GLACIAL DEPOSITS I 19 



which thus far has been observed only inside the territory 

 enclosed by the terminal moraine. The latter owes its forma- 

 tion to a glacier which moved in the direction of the Baltic, and 

 which cannot have exceeded the line occupied by the terminal 

 moraine. The ground moraines before and behind this moraine 

 must belong to two different ice epochs. 



3. The upper bowlder clay of Great Britain contains Scan- 

 dinavian bowlders, and the Scandinavian mer de glace, in this 

 third ice epoch came in contact with the Scottish one. But the 

 ice depositing the Upper Diluvium of the Cimbric peninsula did 

 not quite reach the North Sea ; therefore this Upper Diluvium 

 cannot be of the same age as the Scottish Diluvium of the 

 third ice period, but must belong to a later fourth ice period. 

 We come now to a comparison, if we suppose that the ter- 

 minal moraine of the Baltic range represents the outermost 

 edge of an independent glaciation, differing in point of time 

 from that left behind by the Upper Diluvium of middle north 

 Germany. 



4. The separation is also shown by the appearance of the 

 interglacial formations at Neudeck in West Prussia. 



On the other hand we must remark ( i ) that continual study of 

 bowlders in the different ground moraines has convinced Ger- 

 man geologists, more and more, that no fundamental difference 

 in this respect, is to be found; that, in other words, no single 

 stone can be considered as a guide stone of the ground moraine 

 of a definite ice epoch throughout the whole of its duration. 

 Therefore we must form no far reaching conclusion from the 

 local differences between bowlders belonging to two ground 

 moraines lying one over the other. 



2. Geikie believes that the Finnish terminal moraine is iden- 

 tical in point of time with that of the Baltic range. The line of 

 union which he draws from east Prussia to Finland is, to my 

 knowledge, purely hypothetical, and supported by no observa- 

 tions. I look for the easterly continuation of the Baltic terminal 

 moraine much farther south, in the interior of Russia, and am of 

 the opinion that the Finnish terminal moraine belongs with that 



