ON THE GEOLOGY OF ST. JOHN. 259* 



A section of the Devonian rocks at Perry, Maine, is given by 

 Prof. C. H. Hitchcock, in the Report of the Maine Scientific Sur- 

 vey, 1861, p. 252, which indicate ihree geological epochs. 

 1st Silurian ; 2nd When beds of trap were spread over the up- 

 turned edges of the Silurian strata ; 3rd The period when Devo- 

 nian sandstones were deposited unconformably on the trap. Thi& 

 trap seems to hold the position of. the Bloomsbury beds at St. 

 John. But no evidences of unconformability between the latter 

 deposits and the overlying plant beds have been observed. Prof. 

 Hitchcock therefore surmises that the Perry sandstones may be 

 equivalent to the higher beds at St. John (Cordaite shales and 

 Mispeck group). 



In confirmation of this view, I may remark that the Dadoxylon 

 sandstone thins out both to the southwest and southeast, and not- 

 withstanding its great thickness may be a comparatively local de- 

 posit. Moreover between the highest and the lowest beds of this 

 sandstone, there is a decrease of fifteen to twenty degrees in the 

 dip, showing that a subsidence of the area over which the deposit 

 is spread took place while it was in process of formation. If this 

 oscillation extended to the western part of the Bay of Fundy and 

 no beds corresponding to this sandstone were formed there, a dis- 

 ordance between the dip of the trap and sandstones, such as is 

 exhibited in the section at Perry, would result. 



I have already alluded to a rapid and equally great decrease- 

 in the dip of the beds at the base of the Mispeck group. TJncon 

 formability to the extent of thirty degrees may therefore occur 

 where the highest and lowest of the Upper Devonian beds are in 

 contact. This seems to be the case at Taylor's Island. 



Note by Principal Daioson on some fossils referred to in the above paper, 



Mr. Matthew has forwarded specimens of the Lower Carboniferous 

 and New-Red-Sandstone plants referred to in the above paper. Among 

 the former, I recognise most of the characteristic plants of the Lower 

 Coal Formation of Horton in Nova Scotia, and have no doubt that the 

 beds containing these fossils in New Brunswick, are strictly equivalent. 

 The fossil wood from the New-Red-Sandstone, though not well pre- 

 served, appears to be coniferous, and to have one row of discs on the 

 cell walls, in the manner of the mesozoic pines of the genus Pence or 

 Pinite. 



The discovery of these plants by Mr. Matthew is of great importance 

 in connection with the Devonian flora of the underlying beds ; and it 

 is extremely interesting thus to find, in so limited an area, a rich Deyo- 



