THE IIURONIAN. 29 



papers.* Further, its conglomerates contain pebbles of Laurcntiau 

 rock in the same crystalline state in which these rocks are found at 

 present. It consists chiefly of quartzites, conglomerates of different 

 kinds, limestone, and slates, sometimes chloritic, with interbedded 

 diorite. Without discussing those more or less crystalline rocks 

 west of Lake Superior and in the Appalachian region, which have 

 been by Logan himself and later authors identified with the lluronian, 

 and which may, in part, belong to the interval between the lluronian 

 and Laurentian or to the upper beds of the latter, or may even be 

 later sediments in an altered state, we may attend at once to the beds 

 which on the Atlantic coast succeed the Laurentian. We may 

 remark, however, that, associated with the Huronian at the west of 

 Lake Superior, and extending thence northwards to Hudson's Bay 

 and the Arctic Sea, are the dark slates, sandstones, etc., constituting 

 the Ainiraike series of Hunt. Whether these constitute an upper 

 member of the Huronian or a distinct formation does not certainly 

 appear. It is, however, certain that this formation is very widely 

 distributed, especially in the north, j It is also to be observed that 

 many of the bedded rocks of the Huronian are really of volcanic 

 origin, being bedded volcanic ashes or muds in an altered state. J 



In Newfoundland the older slate-series of Jukes,§ which Murray 

 originally called the intermediate series, but afterwards mapped as 

 Huronian, consists, in ascending order, of quartzites with dioritcs and 

 jaspery bands, slate-conglomerate, green, purple, and red slates, 

 and dark brown or blackish slates. In the upper part of this or the 

 lower part of the next group are the worm-burrows known as 

 ArenicolUes spiralis and the uncertain fossils described by Billings as 

 Aspidella. The lithological correspondence here between Newfound- 

 land and Lake Huron is very close, and is increased by the fact that 

 a series of red sandstones and conglomerates, the Kewcnian of the 

 West and the Upper Huronian or Signal-Hill beds of Jukes and 

 Murray, overlie the typical Huronian in both districts. 1| 



Passing from Newfoundland to the coast of southern New Bruns- 

 wick, we find in the " Coldbrook " and " Coastal " series of Bailey a 

 group corresponding essentially to that in Newfoundland, except, 

 perhaps, in the fact that felsitic rocks occur to a larger extent in the 



* Anniversary Address, 1886. Amer. Jourii. of Science, 1887. 



f G. M. Dawson, " Notes on Nortlierii I'art of Dominion of Canada," Geol. Survey, 

 1887,1). 8; Dr 11. Ball, " Ivcport on lliulsoii l!ay, 1)577 to 188;")," tieol. Survey of 

 Canada. 



t Dawson, Canadian Naturalist, 1857; Nicholson, Quart. Jouvn, Ueol. Soc, 1873; 

 0. M. Dawson, (ieol. Ma;;., 187;i, 



g Keport on Newroniullund, I8l:i. || Geology of Newfoundland, 1881. 



