No. 6.] DAWSON — PALEOZOIC FLORAS OF CANADA. 373 



upper portion of the formatiou, which has the most decidedly 

 Permian aspect, are the following: — 



DaJoxylon materiarium^ Dawson. 



* Walchia (^Araucarites') rohusta, Dn. 

 '^ W. (J..) gracilis, Dn. 



Calamites Suckovii, Brongt. 

 C. Cistii, Brongt. 



* C. Gigas, Brongt. 

 Neuropteris rarinervis, Bunbury. 

 Alefhopteris nervosa, Brongt. 

 Pecopteris arborescens, Brongt. 



* P. rigida, Dn. 



P. oreopteroides, Brongt. 

 ^ Cordaites simplex, Dn. 



Of these species those marked with an asterisk have not yet 

 been found in the Middle or Lower members of the Carbonifer- 

 ous system. They will be found described and several of them 

 figured in my Report on the Geology of Prince Edward Island. 

 The others are common and widely diffused Carboniferous 

 species, some of which have extended to the Permian period in 

 Europe as well. From the Upper beds characterized by these 

 and a few other species, there is a gradual passage downward 

 into the productive-Coal measures, and a gradually increasing 

 number of true Coal-formation species. 



It is worthy of remark here that the association in the Permo- 

 Carboniferous of numerous trunks of Dadoxylon with leafy 

 branches of Walchia and with fruits of the character of Tri- 

 gonocarpa, seems to show that these were parts of one and the 

 same plant. 



(2.) Coal- Formation Suh-Jiora : — 



The Middle or Productive Coal-formation, containins; all the 

 beds of coal which are mined in Nova Scotia and Cape Breton, is 

 the head-quarters of the Carboniferous flora. From this forma- 

 tion I have catalogued^ 135 species of plants; but as several of 

 these are founded on imperfect specimens, the number of actual 

 species may be estimated at 120. Of these more than one half 

 are species common to Europe and America. No less than 

 nineteen species are Sigillarioi, and about the same number are 



* Acadian Geology, and Report on Flora of Lower Carboniferous 1873 



