An August last I made a journey from Moss, through 

 Vaaler, Svindal, Skiptvet, Rakkestad, to the Lakes of Aremark 

 and Ødemark, returning by way of Ørje, Askim, Spydeberg, Ski 

 and Aas to the starting point. This journey was made in order 

 to try to correlate some clay deposits that I had on former 

 occasions found to be fossil-bearing. 



Of these localities none has the classical value of Søreng 

 on the eastern border of Grønsund. (Pl. I). Here, Sårs more 

 than half a century ago made his classical researches. I myself 

 paid a visit to this locality in the summer of 1898 and on a 

 later occasion published a description both of this section and 

 of the neighbouring one of Lekum (Christiania Vid.-Selsk. Skr. 

 I. Math.-Naturvid. Kl. 1908, No. 2, pp. 23—29). The list of fos- 

 sils from the two localities in question, according to the re- 

 searches of Sårs and myself, was, as follows: — 



Anomia ephippium L. var. squamula G. 0. Sårs. 



Pecten septemradiatus Mull. 



Mytilus edulis Lin. 



Nucula tennis Mont. 



Portlandia sp. (? ardica Gray). 



Portlandia lenticula Møll. 



Leda pernula Mull. 



Area glacialis Gray. 



Area pectunculoides Sc. 



Cyprina islandica L. 



Axinus flexuosus Mont. 



Abra longicallis Sc. 



Macoma baltica L. forma typica G. 0, Sårs. 



