20 • JOMAN KIÆR. M.-N. Kl. 



Stratigraphical Results. 



The new fauna is of great stratigraphical interest, being the first one 

 discovered in the sandstone series. 



The age of this series had previously to be determined by its con- 

 nection with the underlying Upper Silurian strata with marine fossils. 

 In my former monography on the Upper Silurian in the Kristiania area^ 

 I have compared the uppermost marine zone in Ludlow, the zone con- 

 taining Leperditia Norvef/ica Kiær (9 g), with the upper part of the 

 Temeside Group in Shropshire. I therefore presumed, that the boundary 

 between the Upper Silurian and the Devonian with great probability 

 might be set directly above this zone. Our whole sandstone series was 

 by this comparison to be regarded as Lower Devonian. 



In consecjuence of this new discovery, however, the question must 

 be taken up again. 



This new fauna is so rich, that an approximate determination of 

 the age might now be possible. As regards Gigantostracs, I have found 

 three species of luir/fpteiiis afid one Pterijijotus. The latter is so frag- 

 mentary, that its relationship cannot be determined. I found two species of 

 Eurypterus, however, in well preserved specimens. None of them agree 

 completely with previously known species, although they are so nearly 

 related to species described from England and Scotland that they give 

 a clear suggestion with regard to the determination of the age: Earyp- 

 terus Norveyicus nov. sp. is then closely related to E. lanceolatus Salt., 

 which form is characteristic of the Downtonian in the Lesmahagow 

 district in Scotland. Further the small Eurypterus minutus nov. sp. is 

 quite closely related to E. pyymaeiis Salt, from the corresponding 

 uppermost part of the Silurian at Kington and Ludlow in Shropshire. 

 I consider the relationship to be so close that in both cases we can 

 speak of vicarious forms. Although species of Eurypterus have been 

 found in certain facies from Wenlock to Devonian, the two Norwegian 

 species seem to indicate the uppermost part of the Upper Silurian that 

 is usually called the Downtonian by English and Scotch authors. 



Such is also the case with the Phyllocarids. I'Vagments of the my- 

 sterious Dictyocaris with characteristic reticular sculpture, which form is 

 very characteristic of the Scottish Downtonian, also occur in large quanti- 

 ties. F'urther fragments of Ceratiocaris have been found, but unfortuna- 

 tely not sufficiently well preserved, to allow of any exact determination 



1 Das Obersilur im Kristianiagebiete, pag. 551 and 538. 



