[MATTHEW j GEOLOGICAL CYCLES IN MARITIME PROVINCES 135 



A fuller exhibit of this cycle is to be found about fifty miles fur- 

 ther east, in a peculiar manifestation exhibiting great numbers of land 

 plants.^ 



This phase of the cycle, as originally described, is as follows^ : — 



FEET, 



Bloomsbury Conglomerate; coarse reddish gray, with beds of 



red slate 500 



Dadoxylon Sandstone; gray sandstone and grit, with beds of 



dark gray shale (from 500 to 2,800) 1,600 



Cordaite Shales and Flags; green and red argillites and dark 

 gray shales^ reddish and gray sandstones, grits and con- 

 glomerates, alternating with argillaceous beds; pale olive 

 green flags and shales, with partings of gray shale 2,400 



4,500 



The two upper divisions of the Mascarene section are wanting in 

 this area., but the thickness of the terrane is more than doubled. 



(The rocks of the Mispec group, which are red conglomerates and 

 argillites, and which, in the Eeport of 1870-71, were associated with 

 this series, have since been found to overlie it unconformably.) 



The Bloomsbury conglomerate and slate, with a part of the Dodoxy- 

 ion sandstone, may be considered as equivalent to the Medina, while the 

 rest of the sandstone division will represent the Clinton black shale. 

 The important member of the Cordaite shales and flags will in this case 

 cover the rest of the Silurian, including, perhaps, the Lower Helderberg 

 Group. ^ 



If the succession of members in this cycle in southern New Bruns- 

 wick, including the plant bed series — Little river Group — be compared 



^ This mass of strata has hitherto been classed as Middle Devonian on 

 account of its plants, so placed by Sir W. J. Dawson, but as will be shown 

 further on, there is no proof of marine forms of this part of the Devonian 

 System either in the plant beds or elsewhere, in all this region. 



2 Rep. Prog. Geol. Surv., 1870-71, p. 170. 



s Some of the leading palaeontologists in the United States, including 

 J. M. Clarke and Chas. Schurchert, now include the Lower Helderberg 

 fauna In the Lower Devonian. Without entering Into the merits of thla 

 question which can only be judged of by an experienced palaeontologist, the 

 writer has continued to include the rocks referred to this horizon in the 

 Maritime Provinces to the Silurian, because of the nature of the deposits and 

 the contained flora, which are nearly uniform with underlying strata and 

 plants, the true Devonian flora not appearing in this district until the age 

 of the Oriskany is nearly or quite reached. 



