72 THE DEVONIAN. 



Report. The restoration given in Fig. 12 will better show the precise 

 character of this curious plant, which, while allied to the club-mosses 

 in structure and habit, has remarkable peculiarities in its fructification. 

 In the case of P. elegans, in which* the fructification is said to 

 consist of " oval scales," these should be understood as flattened 

 spore-cases, not scales. Cyclopteris Jacksoni would also now be 

 placed in my new genus Arckmopteris ; and, as previously stated 

 under the head of Carboniferous, a higher place in the vegetable 

 kingdom might now be assigned to the genus Cordaites on the evi- 

 dence furnished by M. Grand 'Eury. 



The disposition which prevails among European palrcobotanists to 

 refer our Devonian flora to the Lower Carboniferous, proceeds, as 

 already pointed out, in part from their imperfect acquaintance with the 

 development of this system of formations in America, and also from 

 the superior richness, so far, of our flora. But there is not improb- 

 ably another reason. Just as the modern genera of plants seem to 

 have appeared in full force in America in the Cretaceous, while in 

 Europe they scarcely attain a similar development till the Miocene 

 Tertiary, we may have had an earlier introduction of the Palaeozoic 

 flora. This is, I think, now rendered probable by the later publica- 

 tions of Stur and Heer. In any case, however, our Devonian flora is 

 markedly distinct from that of the Lower Carboniferous, as may be 

 seen by reference to the Reports on those floras already referred to. 



9. THE UPPER SILURIAN. 



In the Acadian Provinces, as in some other parts of Eastern 

 America, the great igneous outbursts, evidenced by the masses and 

 dykes of granite which cut the Lower Devonian rocks, make a strong 

 line of distinction between the later and older Palaeozoic. While the 

 Carboniferous series is unaltered, except very locally, and compara- 

 tively little disturbed, and confined to the lower levels, the Upper 

 Silurian, and all older series, have been folded and disturbed and 

 profoundly altered, and constitute the hilly and broken parts of the 

 country. Further, in the Upper Silurian and the older periods, there 

 seems to have been a constant mixture with the aqueous sediments 

 in process of deposition of both acidic and basic volcanic matter, in 

 the form of ashes and fragments, as well as probably outflows of 

 trachyte and dioritic rock, so that all these older formations are 

 characterized by the presence of felsite, and porphyry, and petro- 

 siliceous breccia, and of diorite. Further, since these volcanic and 



* Ac. Geol., 543. 



