HOMOTAXIAL EQUIVALENTS OF THE PERMIAN 341 

 RECAPITULATION 



Returning to the original questions, propounded at the begin- 

 ning, all available evidence appears to indicate : 



I. That while we have in America a great succession of 

 deposits identical in all essential respects to the original Per- 

 mian of Russia, the two great basins merely had similar his- 

 tories that are not necessarily connected, and doubtless were 

 wholly independent of each other and unrelated ; that the Rus- 

 sian Permian constitutes a geological province by itself ; and 

 that therefore the term Permian should not be used as a techni- 

 cally exact term in connection with the Mississippi valley 

 deposits. 



2. That Permian, as originally proposed, applies to a pro- 

 vincial series, and according to our usual standard has at best a 

 taxonomic rank below that of system. Also, in view of the 

 possible elevation of its main subdivisions to the rank of series, 

 the term will have no position in the general scheme of classi- 

 fication. It will be no doubt eventually dropped altogether. 

 The various series belonging to the succession and now hav- 

 ing lower rank, will be considered main subdivisions of the Car- 

 boniferous system. In this country the same plan has been 

 already proposed. 



3. That, with the solution given to the second question, it is 

 unnecessary to attempt to locate the limits of the so-called Per- 

 mian in this country. The divisional lines of the series com- 

 prised in the typical American section in Kansas are already well 

 defined, with the possible exception of that of the uppermost 

 member. 



Charles R. Keyes. 



