1913] SOME CLAY DEPOSITS IN THE S.-E. PART OF NORWAY 17 



Macoma baltica L. forma typica was found in a couple 

 of broken specimens. 



Macoma calcaria Chemn. was rather common as forma 

 typica but occurring as a rule in a relatively small variety. 



Mya truncata L. forma typica G. 0. Sårs was rather 

 common in specimens of a mean size and a mean thickness of 

 the shell, hovvever, mostly broken. 



Zirphaea crispata L. forma typica of a mean size. 

 Rather rare. 



Balanus crenatus Brug., Darw. occurred as a rule as 

 forma typica but sometimes also in a more rugged variety which 

 is also elsewhere found in the shell-banks of Aremark. 



Only a glance at this faunastic list is necessary to as- 

 sure us of the geological position as to stratigraphical age 

 of this fossil-bearing gravel deposit which really belongs 

 to the Littorina-stage. The hypsometrical position of the 

 corresponding terrace limit also coincides with the ancient 

 sea-level of this stage as found some tventy-five kilometres to 

 the north (P. A Øyen: The Quaternary Section of Kilebu 1912, 

 p. 24). Then it is very clear and only a fact of mere conse- 

 quences that shells of Porttandia arctica occurring in this 

 deposit have been washed into the shell-bank itself from an 

 underlying Portlandia-bearmg clay-layer that must be of a 

 younger age than that of the ra-moraine itself. It is, however, 

 interesting to compare this occurrence of arctic shells with the 

 above mentioned one from Horten, only that the comparison 

 will not be quite satisfactory as only one single species occurs 

 near Bjørnestad. The connection may, however, become some- 

 what elucidated by following the fossil-bearing deposits towards 

 the north. 



On a former occasion I published a description of the 

 section through a fossil-bearing deposit near Kilebu (Christiania 

 Vid.-Selsk. Skr. I Mathm.-Katurv. Kl. 1912. Nr. 8) and tried to 

 explain the sequel of layers in that place (1. c, pp. 22—24). 

 A rather curious fact, however, was exposed in that section as 

 layer III which was assumed to correspond with the deposition of 



Forh. 1913. No. 12. 2 



