﻿SUMMARY OF THE CONTENTS. 687 



of this clays (see pp. 149, 150) comprises only a dozen species, 

 nearly all high arctic species, although two {axinus fiexuosus, 

 and macoma baltica) are rather boreal. The predoniinating 

 species are pecten grønlandicus, area glacialis, portlandia 

 lenticula, siplionodeittaliuni vitreum and antalls striolata. 



It may be remarked that portlandia ardica and its ac- 

 companying fauna are never found in this clay, or inside the 

 outer ra ; further it is to be remarked that the form of area 

 glacialis of this clay between the ra-s is not of the hig size of 

 the same species in the older area clay, in which the area 

 glacialis is found up to 18 mm. in length. 



These clays between the ra-s, which can be designated as 

 tJie middle area clay (deposited in deeper water) and the older 

 portlandia clay (so called after the portlandia lenticula, and 

 deposited at minor depths), are found up to about 150 m. above 

 sea-level in Smålenene, and up to about 130 m. in Jarlsberg. 

 Both the fauna and the situation of these clays at a higher 

 level above the sea prove, therefore, that the land has sunk 

 during the retreat from the outer to the inner ra, and during 

 the deposition of the different terminal moraines of the stage of 

 the inner ra. 



Pp. 152—178. D. The Retreat of the Ice-Border from the 



Moraines of the Inner Ra to the Series of Moraines in the 



Kristiania Valley, The Younger Area Clay. 



After the protracted pause at the stage marked by the two 

 series of terminal moraines of the inner ra, the ice-border has 

 retired again more rapidly to the next station, the third great 

 one: the series of moraines in the valleys of Drammen, Lier, 

 Kristiania, etc. These moraines are also stratified and deposited 

 below the sea-level like the ra-s; most of them have dammed 

 up lake-basins behind them. 



The clay-beds deposited during the recession from the inner 

 ra-stage to the third great stand-still have been especially well 



