156 A. p. COLEMAN 



earning railroad near mile 100, and on the Tretliewey silver-mining 

 location; both localities being included in the same area of conglom- 

 erate as mapped by Professor Miller. vSearch was made for glaciated 

 stones near Temagami, twenty-eight miles southwest, where the con- 

 glomerate is prominent in railway cuttings, but the rock proved to be 

 somewhat squeezed and decidedly more metamorphosed than at 

 Cobalt, so that the stones broken out of the matrix showed no well- 

 preserved surfaces. In every other respect the conglomerate is exactly 

 like that of the silver region. 



Conglomerates of the same age are known from almost every area 

 mapped as Huronian in Ontario, from Lake Temiscaming on the 

 east to Lake-of-the-Woods on the west, a distance of more than 700 

 miles; and from Lake Huron on the south to the north end of Lake 

 Nipigon, 250 miles. In my own field-work such conglomerates have been 

 studied at more than twenty localities scattered over the great region. 



In most cases the conglomerate has proved to be far more meta- 

 morphosed than at Cobalt, often transformed into schist conglomerate 

 with the pebbles and bowlders flattened into lenses. In such cases 

 the resemblance to bowlder clay is lost, though the varied size and 

 lithographical characters of the stones, and often also their wide 

 spacing in the matrix, are suggestive of a glacial origin. 



In several places, however, the Lower Huronian conglomerate is 

 almost as unchanged as at Cobalt, for instance, near Lake Wahnapitae, 

 east of Sudbury, and at various places in the typical Huronian region 

 north of Lake Huron. Years ago these impressed me as resembling 

 bowlder clay, but at that time no striated stones were found. 



These areas of characteristic tillite occur at points 200 miles apart, 

 about in lat. 46°. Of the other conglomerate areas one can only say 

 that in all probability they are glacial also. In some places where the 

 pebbles form closely crowded bands and are fairly uniform in size 

 they are probably water formed, and may be explained as kames or 

 marginal gravel beds like the Saskatchewan gravels of Alberta, glacial 

 materials rearranged by rivers or by wave action. 



Very similar bowlder conglomerates are described from Huronian 

 regions not visited by the present writer. Dr. Bell maps schist con- 

 glomerates in northern Quebec, the most easterly at Mattagami Lake, 

 in long. 77° 30', and Mr. Low describes bowlder conglomerates from 



