Till-: I.AUrj-.NTIAN. 3;j 



on both sides of the Athmtic those grciit loklings \vhii:h have bent 

 and crumpled the ohl crystalline rocks secin to have occurred at the 

 close of the Laurentian and before the next succeeding formation. 

 It is to be observed here, however, that in the case of the Laurentian 

 these foldings pervaded the whole of what are now the Continental 

 areas, as well as those marginal lines which were alone affected by 

 the succeeding movements. This general disturbance of the Lau- 

 rentian over the whole breadth of our continents, before any of the 

 succeeding beds were deposited, impresses us with the conviction that 

 the earth-movements immediately following the Laurentian were 

 more extensive than those of any subsc(ineiit period, that they form 

 a sufficient explanation of the very different character of the next 

 succeeding formations, and that they produced wide areas of elevated 

 rock which formed the nuclei of all later depositions and movements. 



In comparing the Upper Laurentian of New Brunswick with the 

 I'ocks which elsewhere, as in New Hampshire,* the district of St 

 Jerome, the Madoc district in Ontario, and the country west of Lake 

 Superior, rest on the older Laurentian gneisses or on rocks regarded 

 by some as primitive granites, one is obliged to admit either that 

 this formation is of a somewhat protean character, or that, as Hunt 

 maintains, there are several different formations of post-Laurentian 

 crystalline rocks occurring in these different localities. 



In the Lewisian gneiss of Murchison we have in Britain an ade- 

 quate representative of the Lower Laurentian, and in the two members 

 of the Dimetian of Hicks a sufficient parallel to the middle and 

 upper members of this great series,-]- which undoubtedly also appear 

 in the isolated mass of the Malverns, and have been recognised l)y 

 Barrois and Bonney in the ancient crystalline rocks of Brittaiiy.| 



The following may be reproduced with some changes from tlie 

 supplement of 1878, as indicating the correlation of the older rocks 

 of Acadia with those of Western Europe. 



England, &c. 



Nova Scotia and Nf.w 

 Brun.swick. 



Siluriajj. 



Ludlow, W'enlock and Llandovery, 

 or Mayliill. 



Upper Arisaipc Series, Nova Scotia ; 

 Upper Mascarene Series, New Hruns- 

 wick ; Lower Arisaip:, New Canaan, and 

 Wentwortli beds of Nova Seotia; and 

 I Kestigoucho Series, New Hrunswiek. 



* Hitchcock's Report. Tlic beds called Montalhan by Hitchcock .leeupy tills 



jiosition. 



t Ilicks's "Classification of Kozoic and Lower Piiia'ozoic IJocks," Popular 



Science Review, 1881. 

 t IJonney, Quart. Jourii. Ce.d. Soc, vol. xliii. 



