64 ROYAL SOCIETY OF CANADA 



which they once formed a part, as is found in connection with nearly all 

 the systems from the Pre-Cambrian to the Trias, and especially marked 

 in connection with Silurian and Carboniferous outliers. It is seen yet 

 again in the maturely dissected character of the whole region, in the 

 form and dimensions of both its hills and valleys, in the deep burial of 

 the lower slopes of the northern hills by fragmentai deposits derived 

 from the latter, and in the vast number of felsite blocks derived 

 from these same hills which strew the beds of most of the northern rivers. 

 The subject of early erosions in New Brunswick' has been discussed at 

 some length by the writer in the memoirs of this Society.^ 



III. Glaciation. — In a region so well within the area of Quaternary 

 glaciation, it is not remarkable that the evidences of the latter should be 

 found on every side, and that the events of the period should have had 

 much to do with the determination of modern surface features. 



The first effect attributable to ice movement was that of a plough- 

 ing of the surface. Not only is this seen in the general distribution of 

 glacial stride and the occasional but not frequent occurrence of roches 

 moutonnées, but in the broadening and deepening, perhaps in the occa- 

 sional formation, of valleys. Where obstacles to the general movement 

 of the ice lay in its path, it would naturally be deflected and such troughs 

 as that occupied by Nictor Lake, just north of Bald Mountain, the valley 

 of Pratt's Brook, just north of Tweedside, in York county, and the course 

 of the Magaquadavic valley around the escarpment west of Oromocto 

 Lake, may indicate deflections of this kind. As proof of valley evcava- 

 tion may be instanced the fact that the rock bottom of the valley of the 

 St. John river at Fredericton is 300 feet or more below its present bot- 

 tom, the interval being occupied by Pleistocene clays holding the remains 

 of fresh-water plants and fishes. Many valleys or sections of valleys are 

 no doubt of pre-glacial origin, but many others are post-glacial, and it 

 is easy to see that in many cases streams are now flowing wholly or in 

 part along courses different from those which they once occupied. This 

 is largely the result of a second feature in connection with glaciation, 

 i.e. the wide transfer and accumulation of loose matter. By this in many 

 instances old channels have been obliterated and new ones determined, 

 as in the well-known instances of the Gfrand Falls of the St. John, the 

 Aroostook Falls, the Meductic and that near the city of St. John. The 

 distinction between pre-glacial and post-glacial channels in New Bruns- 

 wick and the changes in the river systemB of the latter in later geological 

 times has been the subject of lengthened and careful study by Prof. W. 

 F. Ganong, the results of whose investigations will be found in the 

 Bulletins of the Natural History Society of St. John. In addition to 



1 Proc. and Trans. Royal Society, 1st Sories, Vol. II, 1884. 



