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the Lewisian gneisses of the North-west Highlands of 

 Scotland. On the other hand the lustrous pelitic gneisses 

 rich in mica, or other hydro-micaceous minerals probably 

 belong to the Grenville group as in the case of the Highland 

 schists of Scotland, or the Telemark formation of Norway. 

 In many gneisses there is a distinct ribbon-like, or banded 

 character, in which parallel bands of different composition, 

 often quite thick, extend for long distances along the strike. 

 The writer would suggest that this is due to an original 

 difference in the material caused by the sorting action of 

 water or other agency. 



Both of these gneisses are cut in numerous places by 

 granite dykes, many of which are pegmatitic. It is from 

 these great pegmatitic dykes that the potash feldspars are 

 mined in large quantities for use as glazes for earthenware. 

 These dykes occur in great numbers, and two of the pro- 

 ductive ones are included in the excursion programme. 

 There is little doubt that most of the interesting minerals, 

 so well developed in this area, are due in large measure to 

 the metamorphism produced by these intrusives, or to 

 solutions and gasses which accompanied them. 



These occurences have been excellently exposed by 

 the glaciation of Pleistocene times. This was sufficient to 

 remove all the weathered material from both hill and hollow, 

 so that the old contour of the Pre-Cambrian is preserved, 

 while its surface is made quite fresh again for detailed study. 

 There has not been sufficient time since glaciation for any 

 appreciable weathering, so that all the occurrences are now 

 seen at their best. The effects of the glaciation are in 

 themselves interesting. The famous Glacial Gardens of 

 Lucerne, Switzerland, scarcely surpass the examples of 

 glaciation to be seen immediately about Kingston. 



The Paleozoic portion of the area is an irregular fringe 

 along the south-west flank of the Pre-Cambrian. The 

 number of outliers of sediment scattered over the Pre- 

 Cambrian suggests that they at one time completely 

 covered it in this portion of the Dominion, but have been 

 removed by denudation. These lie almost horizontally, 

 dipping only 6 to 9 degrees to the south-west. They are 

 for the most part, clean limestones running as high as 96 

 per cent calcium carbonate. They are shaly in a few places, 

 but, as a rule, very compact, affording an excellent building 

 stone. A reddish sandstone is found as the lowest member 

 of the series, and is tentatively correlated with the Pots- 



