70 



THE DEVONIAN. 



terest, as sliowing perhaps more of the land life of the period, and 

 more especially of its flora, than the Devonian of any other part of the 

 world. Jn connexion with this, it is to be observed that the va.st 

 development of this formation in the great Lake Erie district shows 

 mainly its marine conditions. Yet it is satisfactory to know that 

 Professor Hall finds erect trunks of tree-ferns and abundance of 

 remains of fern fronds and Psilophyton in the Chemung sandstones of 

 New York, and that in the marine limestones of Ohio Dr Newberry 

 has discovered trunks of conifers and beautifully preserved stems of tree- 

 ferns. The vague notions which many European geologists still enter- 

 tain as to the importance and extent of the Devonian period would be 

 at once corrected could tliey study the American developments of it. 

 The following table will show the nature and distribution of the 

 formations referred to : — 



These rocks in the Acadian Provinces overlie the fossiliferous beds 

 of the Lower Helderberg or Ludlow group, and underlie the Lower 

 Carboniferous, to the peculiar flora of which I have already referred. 

 Fi"om these beds, thus limited, I have described or catalogued 125 

 species of fossil plants,-f- of which the greater part are specifically, and 

 some generically, distinct from those of the Lower Carboniferous. 

 A very considei'able proportion of thebc plants have been derived 



* On the evidence of fossils, Hall now regards the Oriskany as Silurian. It is 

 really a group of transition, and in Canada its physical relations are with the Devonian, 

 and it introduces the fauna and flora of that age. 



f Eeport on Fossil Plants of Devonian, etc.. Geological Survey of Canada, 187L 



