120 K. KEILHACK 



of middle Sweden and southern Norway, a view which is shared 

 by Herr Vogt in Christiania. 



3. It seems to me unnecessary entirely to repudiate the 

 opinions of the north-German geologists in order to explain the 

 occurrence of Scandinavian bowlders in the upper bowlder clay 

 of Great Britian. It remains also to be proved that these Scan- 

 dinavian bowlders have not been taken from the terminal 

 moraines of the second ice period and incorporated in the drift 

 of the third, and it may also be questioned whether the ground 

 moraine of Scotland with northern bowlders really belongs alto- 

 gether to the third glacial period, or whether the connection of 

 the Scandinavian with the Scottish ice in the third glacial period 

 is more than imaginary. I am prompted to raise these ques- 

 tions, because there are extremely weighty reasons against the 

 acceptation of the Baltic terminal moraine as the outermost 

 extremity of a separate (fourth) glacial epoch. On the con- 

 trary, the similarity in age of this moraine with the so-called 

 upper bowlder clay of the Mark, Posen, etc., seems undisputed. 

 I will state these reasons more definitely. 



Of the terminal moraine of the Mark-Brandenburg, seventy- 

 five square kilometers have been carefully mapped (scale: : 25,000) 

 by the geological survey, and the investigation and surveying of 

 the bordering territory on both sides reaches almost to Stettiner 

 Haff in the north, and nearly to the northern edge of Lausitz in 

 the south ; therefore the territory investigated stretches in round 

 numbers seventy-five kilometers from the terminal moraine in 

 both directions. I have myself mapped a strip of country in the 

 territory of the Baltic range between the Oder and Vistula 

 extending thirty-four kilometers from east to west, and lOO 

 kilometers from north to south. The terminal moraine passes 

 through this strip for a distance of forty-five kilometers, and a 

 territory twelve to twenty-four kilometers in breadth south of 

 the terminal moraine is included within it. I have also by gen- 

 eral surveying of the 500 kilometers of terminal moraine between 

 the Oder and the Vistula, crossed the range in many places. 

 All this work, and particularly the special mapping of about 



