_Dadoxylon materiarium_, Dawson. * _Walchia_ (_Araucarites_) _robusta_, Dn. * _W._ (_A._) _gracilis_, Dn. * _W. imbricatula_, Dn. _Calamites Suckovii_, Brongt. _C. Cistii_, Brongt. * _C. gigas_, Brongt. _Neuropteris rarinervis_, Bunbury. _Alethopteris 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 Carboniferous system. They will be found described, and several of them figured, in my "Report on the Geology of Prince Edward Island."[FK] 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, characterised 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. [FK] 1871. It is worthy of remark here that the association in the Permo-Carboniferous of numerous trunks of _Dadoxylon_ with the branches of _Walchia_ and with fruits of the character of _Trigonocarpa_, seems to show that these were parts of one and the same plant. This formation represents the Upper Barren Measures of West Virginia, which are well described by Fontaine and White,[FL] and the reasons which these authors adduce for considering the latter equivalent to the European Permian will apply to the more northern and eastern deposits as well, though these have afforded fewer species of plants, and are apparently less fully developed. [FL] "Report on the Permian Flora of Western Virginia and South Pennsylvania," 1880. (2) _Coal-formation Sub-Flora_: The Middle or Productive Coal-formation, containing all the beds of coal which are mined in Nova Scotia and Cape Breton, is the headquarters of the Carboniferous flora. From this formation I have catalogued[FM] one hundred and thirty-five species of plants; but, as several of these are founded on imperfect specimens, the number of actual species may be estimated at one hundred and twenty. Of these more than one half are species common to Europe and America. No less than nineteen species are _Sigillariæ_, and about the same number are _Lepidodendra_. About fifty are ferns and thirteen are _Calamites_, _Asterophyllites_, and _Sphenophylla_. The great abundance and number of species of Sigillariæ, Lepidodendra, and ferns are characteristic of this sub-flora; and among the ferns certain species of _Neuropteris_, _Pecopteris_, _Alethopteris_, and _Sphenopteris_ greatly preponderate. [FM] "Acadian Geology," and "Report on Flora of Lower Carboniferous," 1873.