wHiTEAVEs.] DEVONIAN FOSSILS, MACKENZIE RIVER BASIN. 251 



Ten of the apecies occur also in Iowa, in beds that are now referred 

 to the ChemunL^. 



These are : — 



Oampophyllum ellipticum. Spirifera cyrtln.eformis. 



Hederella Canadensis. Atrypa reticularis. 

 Productella dissimilis. " " var. aspera. 



Orthis striatula. (=0. iowensis.) Rliynrlionella pui,'nus. (=R. alta.) 



Strophodonta demissa. Cryptonella Calvini. 



Seven are identical with species thai are said to bo charncteristio of 

 the Chemung of the States of New York and Pennsylvania. 



These are: — 



Troductella lachrymosa, var. lima. Leptodesma Demus. 

 Spirifera disjuncta. " .Tason. 



Athyris Angelica. Schizodus Chemungensis. 

 Ehynchonella cuboides. (venustula.) 



In the Mackenzie River district, however, the subdivisions of the 

 Devonian System that exist in the State of JSTew York and Ontario are 

 probably not recognizable, and there are strong reasons for supposing 

 that the whole of the fossils reported ujjon in the.se pages belong to the 

 " Cuboides Zone.'' 



It is true that Ithynclwnella cuboides itself has so far been found only 

 on the Peace and Hay Rivers, where it is invariably associated with 

 Spirifera disjuncta (or Verneuili), but other fossils eminently charac- 

 teristic of the Cuboides Zone will be noticed in nearly all the fore- 

 going lists of species from the Athabasca and its tributaries or from 

 the Mackenzie. 



In a paper published as a Bulletin of the Geological Society of 

 America and dated May, 1890, Prof H. S. "Williams cites three species, 

 which, according to Kayser, are the "principal fossils of the Cuboides 

 Schichten'' in Kurope, and thirteen others as "conspicuous fossils in 

 its fauna." Of the first three, two are RhynchoneUa cuboides and Spiri- 

 fera disjuncta (or Verneuili,) which, as before stated, occur together at 

 the Peace and Hay Rivers. Of the thirteen others, five, viz., Produc- 

 tella subaculeata, Orthis striatula, Atrypa reticularis, RhynchoneUa pugnus 

 and Pentamerus galeatus are found in one or other of the lists of species 

 on pages 247-50. Pachypora cervicornis, too, which was collected at 

 the " Ramparts " by Mr. R. W. McFarlane in 1857, and Strophalosia 

 productoides, which has since been found by Dr. Bell and Mr. McConnell 

 in the Devonian rocks of the Athabasca, are both stated to be charac- 

 teristic of the Cuboides Zone in Europe. The Oyathophyllum hexagonum 

 of the Cuboides Zone of Belgium is represented at the " Ramparts " by 



