316 Miscellanies. 



volume of plans of various lakes and rivers between Lake 

 Huron and trie River Ottawa. Toronto, 1857. — This Report 

 covers four years of exploration. As in all the labors of the au- 

 thor, there is evidence of careful research and sure progress. Tho 

 Special Report of Sir W. E. Logan covers the first 50 pages. It 

 takes up especially the arrangement of the crystalline limestone 

 among the other Laurentian (Azoic) rocks, and especially its con- 

 dition in the vicinity of Grenville. The limestone occurs in bands 

 that are nearly parallel, and which are so related as to leave no 

 doubt that one or more strata of limestone are there folded up 

 among the crystalline rocks. In Grenville there are two such bands 

 about two miles apart, having a N.N.E. strike, and dipping, like 

 the included gneiss, to the N.N.W. 50° to 70°. To the rear of the 

 township the two unite andhave a thickness of 500 to 1000 feet. 

 Other similar bands and patches occur to the northward and east- 

 ward of these, which have approximately the same strike, and 

 confirm the view that the Azoic rock of the region, before its 

 crystallization, contained one if not two or more thick strata of 

 limestone. The author discusses the precise character of these 

 folds and illustrates the subject by means of a map of the region 

 on which the bands of limestone are represented in color. 



"The Reports of A. Murray for the years 1853 to 1856 occupy 

 pages 59 to 190, and contain details respecting the topography 

 and geology of the region west of the Ottawa and north of Lake 

 Huron. These are followed by Mr. James Richardson's Report 

 on the Island of Anticosti, and the Mingan Islands in the Gulf 

 of St. Lawrence, and the Palseontological Report of E. Billings, 

 Esq. The island of Anticosti is covered by fossiliferous starta re- 

 ferred to a period uniting the Lower and Upper Silurian ; the 

 rock is an argillaceous limestone 2300 feet in thickness, through- 

 out conformable and nearly horizontal. E. Billings, Esq., observes, 

 p. 249, "All the facts tend to show that these strata were accu- 

 mulated in a quiet sea, in uninterrupted succession during that 

 period in which the upper part of the Hudson river group [Lower 

 Silurian], and the Oneida conglomerate, the Medina sandstone 

 and the Clinton group [Upper Silurian], were in the course of be- 

 ing deposited in that part of the Palaeozoic ocean now constitut- 

 ing the State of New York and some of the countries adjacent.' 

 The fossils of the middle portion fill up the blank with the Upper 

 and Lower Silurian, combining many of the Hudson river group 

 with those of the Clinton, with the addition of other species un- 

 known to both. 



