1913] SOME CLAY DEPOSITS IN THE S.-E. PART OF NORWAY 29 



III of the Kilebu section. Consequently part IV of the Kilebu 

 section must necessarily be correlated with the first part of the 

 Sveneng intraglacial stage. As we previously learned, however, 

 part IV of the Kilebu section really consists of three different 

 layers (I. c. p. 5), and these three layers together with the layers 

 V and VI form a series quite analogous to a couple of younger 

 series of the same section, viz. X — XIV as the middle one, and 

 XVIII— XXII as the upper one. In this way such a conformity 

 to law is pronounced as well in these three series as in the 

 two series separating them that really no other correlation may 

 seem possible than that of which I gave an exposition in 

 the above mentioned paper (1. c, pp. 22 — 24). Then it becames 

 clear that in the Kilebu section the first 'scarce fragments of a 

 very small variety of Mytilus edulis' are just met with at the 

 beginning of the Sveneng stage accompanied with such species 

 as Pecten islandicus Mull., Mya truncata L. var. uddeval- 

 lensis, Macoma calcaria Chemn., and Balanus crenatus 

 Brug., Darw. 



Now, we may proceed in discussing the occurrence of the 

 three above mentioned species, Pecten septemradiatus, Ma- 

 coma baltica and Mytilus edulis. As to the occurrence of 

 the first one of these species, viz. Pecten septemradiatus we 

 have only to note that as well its way of immigration as the 

 probable age of this immigration make this species a rather 

 close companion of Portlandia lenticula and Area pectun- 

 culoides. And, in its turn Macoma baltica joins the company 

 as a conspicuous representative of the Littorina-stage. As to 

 the occurrence of the last mentioned species, viz. Mytilus edulis, 

 we may only notice the rich occurrence of this species during the 

 Mytilus-stage. On a lower level, however, the rich occurrence 

 of large specimens of this species in clay deposits as a rule 

 indicates shallow-water deposition of the age of the Pholas-stage. 

 As far, I suppose, we have now considered most of the clay 

 deposits that in this distnct are due to be regarded in connection 

 with the immediate question now before us. 



