I916. No. 10. THE LOWER CAMBRIAN HOLMIA FAUNA. 99 



Paradoxides sp. Small., incomplete fragments, showing fine granu- 

 lation and short raised lines. 



Acrothele cf. gramilata Lnrs. 



Lingulella cf. Xatliorsti Walc. 



Microiiiitra sp. 



Toreliella /aez'igata Lnrs. 



We can scarcely doubt that this is a transition fauna between the 

 Lower and the Middle Cambrian. It is specially interesting to note 

 the occurrence of Toreliella laevigata Lnrs., one of the most conspicuous 

 Lower Cambrian forms in Scandinavia. 



I therefore consider it proved that the Lower Cambrian fauna in this 

 region passes without any sharp line of distinction into the Middle Cambrian, 

 a circumstance of considerable interest that it is to be hoped will be further 

 elucidated by continued investigations. 



As long since demonstrated, the Lower Cambrian gre3--green shales 

 lower down pass over to what are called the Sandstone shale with trails. 

 This zone consists of thin strata of quartz sandstone, the lower side of 

 which often shows formations resembling trails. Between the layers we 

 often find grey-green shales, to some extent onl}' as deposits of shale 

 on the plates. Beneath this, apparently without interruption, there follows 

 the Quartz sandstone^, a huge series of thickly banked quartz sandstone, 

 to which we shall refer later on. The Sandstone shale constitutes the oldest 

 zone in which fossils have been found. As we have mentioned J. Bras i ad 

 found a specimen of Toreliella laevigata in an ellipsoid of calcareous sand- 

 stone in Krokviksbugten, and O.E.Schiøtz ^ farther to the east by the Glommen 

 and in a corresponding level found two badly preserved Hyolitltus forms. 

 Beneath this zone all remains of marine animal life disappear. 



II. Our Lower Cambrian Beds and their Limits. 



In an earlier section we considered the fossil-bearing zones that may 

 be distinguished in the upper part of our Lower Cambrian formations ; we 

 will now pass over to a investigation of the general limits of our Lower 

 Cambrian. 



In the district at Ringsaker, which we have specially dealt with in 

 the present work, the grey-green shales with their 3 fossil zones constitute 



^ See especially: Th. Münster, tekst til kartbladet Lillehammer, Norges Geol. Unders. 



No. 30, 1900. V. M. Goldschmidt, Profilet Ringsaker Brøttum. Norges Geol. Unders. 



Aarb. 1908, No. 2. 

 - O. E. ScHioTZ, Den sydostl. del av Sparagmit-kvartzfjeldet i Norge. Norges GeoL 



Unders. No. 35. 1902. 



