196 Canadian Record of Science. 



The Cambric Dictyonema Fauna of the slate belt 

 of Eastern New York. 



By Rudolf Rudemann. 



[N. York State Museum Bulletin 69, 1902 (1903) ]. 



This paper is of much interest to American and Cana- 

 dian geologists as it contains a very full discussion of the 

 relation of the Dictyonema Zone to the Cambrian and 

 Ordovician systems. 



The author gives an account of the position of this 

 band in Scandinavia, and the elaborate studies Linnarsson, 

 Tullberg, Lundgren and Brogger upon its fossils, and^ its 

 relation to the Cambrian types below and Ordovician 

 above. " The northern European paleontologists, almost 

 without exception, have agreed " to place this band as the 

 " termination of the primordial [Cambrian] fauna." 



On the other hand the English geologists, including 

 Prof. Geikie, still include in the Cambrian the next group 

 (Tremadoc) above this band, though Brogger and others 

 show that the paleontological evidence is against such a 

 decision. This use of the term Cambrian is based on 

 historical usage, and the acceptance of the Areing fauna 

 as the base of the Ordovician. 



Dr. Eudemann, from the conditions at Navy Island, in 

 the St. John basin, finds evidence (shown by Matthew) 

 that the Dictyonema Zone should be included in the 

 Cambrian ; but he holds with the continental paleontolo- 

 gist that the divisional line for the summit of the 

 Cambrian should be drawn at the top of this Zone. He 

 alludes in terms of approval to the work of Ells and Ami 

 on the rocks of the Quebec Group in the typical region, 

 but he probably misunderstands Ells' table of the divisions 

 in these rocks in attributing the two lower to Lower 

 Cambrian on account of remains of Olenellus Thompsons. 

 Ells' meaning probably is that the fossils are contained in 



