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DE. J. W. DAWSON ON NEW 



palaeobotanists as Lower Carboniferous, apparently on no better 

 grounds than their superior richness in plants to the Devonian of 

 Europe. On this account it may be desirable here to summarize 

 the evidence now available as to their actual age. This may be 

 stated thus : — (1) The Dadoxylon Sandstone and Cordaite shale 

 of Southern New Brunswick are folded up and partially altered with 

 the Silurian and Cambrian rocks of the district, and are overlain 

 un conformably by the Lower Carboniferous conglomerates (Subcar- 

 boniferous of some American geologists). These conglomerates are, 

 further eastward, associated with beds holding the characteristic 

 fossil plants of my Horton series, equivalent to the Tuedian or 

 Calciferous series of Scotland. There is also evidence that the 

 Devonian plant-beds are anterior to the great intrusive Devonian 

 granite of this region, whose debris are found in the Lower Carbo- 

 niferous conglomerates, but not in the underlying rocks. Additional 

 facts illustrative of these points will be found in the Reports of 

 Messrs. Bailey and Matthew in the publications of the Geological 

 Survey of Canada for 1871 and 1875. 



(2) The flora of these beds is markedly different from that of the 

 Lower Carboniferous, of the Millstone Grit, and of the true Coal- 

 formation in New Brunswick and Nova Scotia, all of which have 

 been studied and described. 



(3) The prevalent forms in the St. -John beds are those character- 

 istic of the Devonian in Gaspe, New York, and Maine, such as Archce- 

 ojoteris, Cyclopteris obtusa, Psilophyton, Catamites radiatus, Dadoxylon 

 ouangondianum, though several genera are common to these beds and 

 the Carboniferous. The fact that the flora of these beds is richer 

 than that of the European Devonian, and contains types which 

 appear later in Europe, is in harmony with known facts as to the 

 earlier appearance of plants in America in other stages of geological 

 history. I may add that some of the genera noticed in 1863 from 

 St. John, and not then known in the Devonian of Europe, have sub- 

 sequently been found there. Even as late as 1879 some of them 

 were discovered by Peach in the Old Bed of Scotland. 



(4) The new facts which have been disclosed, more especially those 

 which indicate the great richness of the Devonian flora of New York 

 in Ferns, now induce me to believe that these St. -John beds, though 

 rivalling the Coal-formation in their abundance of fossil plants, are 

 really of the age of the Hamilton group of New York, which in 

 Europe would be regarded as Middle Devonian. 



(5) I would further add that the richness of this flora in species, 

 as well as the discovery of rare and exceptional forms, such as insects, 

 is in part due to the excellent exposure of the beds in the vicinity of 

 St. John, and in part to the extensive and thorough nature of the 

 explorations carried on with the aid of blasting by Messrs. Hartt 

 and Matthew, under the auspices of the Natural-History Society of 

 New Brunswick. It is probable that few fossiliferous beds in the 

 world have been so thoroughly explored. In connexion with this 

 it is to be observed that the mass of the specimens obtained repre- 

 sents only a few species, while the greater number are represented 



