1913] THE QUATERNARY SECTION OF FOSS 17 



Only in some scattered places a faint reaction lo HG1 may be 

 detected. In the upper part of this section, however, the clay 

 material is very much mixed with fine sand; this deposit also 

 has a yellowish-grey colour and proved to have been laid down 

 in thin layers of a thickness between one millimetre and half a 

 centimetre. Even in this deposit thin sand-layers may be seen 

 as separating layers of sandy clay. In other portions of the 

 deposit, however, sand is seen to become conspicuously predomi- 

 nant. No reaction to HC1 is to be discovered. 



The different sections above described may be traced more 

 or less continuously and they may in many cases be connected 

 by intervening ones often forming the missing link for a clear 

 interpretation. 



As no fossils have been found neither in series XX of 

 section F nor in section G it is not easy to tell the geological 

 age of the upper part of the last mentioned section. In the sur- 

 roundings of this section, however, some younger strata were also 

 seen, viz. some shallow-water material or such material that has 

 been washed from the surrounding terraces. In the lower part 

 it was of a yellowish-grey colour and more clayey character, in 

 the upper part, however, it had a grey colour and was formed 

 of a sandy material. 



Quite near to the section G a very interesting section, H, 

 is exposed quite continuously in the direction towards the river. 

 In the lower part of this section the layer corresponding with 

 the upper part of section G proves to have been seriously eroded 

 in a belt lying at the level of 26,2 metres above sea or the da- 

 tum line of the harbour of Christiania. The depression caused 

 by erosion is filled with a series of strata forming true littoral 

 ] ayers as proved as well in their structure as in the character 

 of the material. The lowest one of these layers forms a deposit 

 of coarse gravel with numerous stones; it is rather well assorted 

 and of a grey or reddish-brown colour. It has a thickness of 

 about two decimetres or in some places even about half a meter, 

 but is wedges completely at the level of the erosion line and 

 also very nearly in the direction of the river. This layer is 



Vid.-Selsk. Forh. 1913. No. 2. 2 



