272 Canadian Record of Science. 



Since the palteontological correlations that Mr. Fletcher 

 finds so misleading are largely based on the evidence of 

 fossil plants ; and since he does me the honor to mention 

 my opinions regarding the equivalents of several of the 

 Upper Palceozoic formations, I herein present somewhat 

 more definitely the pala3ontological evidence as seen from 

 my own standpoint. At the same time a seeming discrep- 

 ancy between one of my correlations and that of the same 

 flora by Mr. Kidston, whom Mr. Fletcher also quotes, will 

 be explained. 



From the outset it must be borne in mind that I per- 

 sonally have not visited the region in question, and the 

 views expressed regarding the ages of several of the Nova 

 Scotia plant beds are based exclusively on paleeontological 

 evidence, interpreted in accordance with our knowledge of 

 the fossil floras of the Appalachian province or of Europe. 

 Keasoning from the observed vertical and horizontal dis- 

 tribution both of identical and of related genera and 

 species, and especially from the stratigraphical occurrence 

 of identical or essentially identical floras, I shall state (1) 

 what, in my judgment, are the approximate positions of 

 the respective plant beds as naturally indicated by the 

 floras, and (2) the maximum of time latitude within which 

 the floras should fall. The correlations are theoretical, 

 and may be slightly modified by local stratigraphical 

 conditions. Such a method is liable to error, but the 

 errors, if the conclusions are based on ample fossil mate- 

 rial, should fall within reasonable limits of proximity to 

 the truth. Surely the coefficient of error should not be so 

 great as to permit an entire geological-period to intervene 

 between its pakeontologically theoretical position and its 

 actual place. 



Only those portions of the formations actually furnish- 

 ing the plant material are included in this discussion. It 

 is conceived that the time interval represented by one or 

 more of the enormously thick subdivisions of the Nova 



