178 Reviews — Oeological Survey of Canada. 



tbe western part of the area survej'ed and producecl southward 

 through La Cloche Island and the eastern end of Grand Manitoulin 

 Island, it would exhibit the following ascending succession : — 





Feet 



Chocolate marls and fine sandstones (Chazy ?) .. 



100 



Trenton group 



320 



TJtica formation ... 



60 



Hudson River formation 



250 



Clinton formation 



177 



Niagara formation 



405 



Guelph formation (?) 



100 



1,412 



The Laurentian rocks met with consisted of mica- and hornblende- 

 gneisses in even and regular beds, together with coarse hornblende- 

 and mica-schists and bands of quartz-rock with schistose partings. 

 These dip usually at angles of medium inclination. 



The most conspicuous feature of the Huronian system is a whitish 

 quartzite which forms great ridges extending eastward from a point 

 on the mainland north-west of Georgian Bay, and again in a south- 

 westerly direction to Lake Huron. Between these two arms of the 

 quartzite, and northward, the most abundant rock is greywacke, 

 which is associated with varying quantities of quartzites, quartz- 

 conglomerates, agglomerates, breccias, sericite- and mica-schists, 

 impure dolomites, and eruptive greenstones. The whole series, 

 including the quartzites, dips at high angles. 



The economic minerals in this region include iron, copper, and 

 nickel, but they are not in sufficient quantity to encourage mining 

 operations. 



Mr. A. P. Low's report is based upon a traverse of the northern 

 part of the Labrador Peninsula, from Richmond Gulf (Hudson Bay) 

 to Ungava Bay (Hudson Strait). The route taken lay through Clear 

 Water and Seal Lakes and the Stillwater, Larch, and Koksoak 

 Rivers, the last-named emptying into Ungava Bay. The text is 

 illustrated by remarkably good reproductions from photographs, 

 from which a vivid idea is formed of the essentially barren nature 

 of this northern wilderness. 



Some general examination into the geology of the country was 

 obtained as time and opportunity pei'mitted, the object being to 

 supplement the results of the explorations of 1892, 1893, 1894, 

 and 1895 in this region embodied in the Report on the Labrador 

 Peninsula. 



Laurentian rocks were met with along the greater part of the 

 route. They consisted chiefly of more or less foliated granite, and 

 of eruptive masses of dark -greenish basic granite and diabase. 

 The contact between the Laurentian granite and the stratified and 

 unaltered rocks of the Cambrian is concealed by the deep clays of 

 the valley of Junction River, where the western wall of the valley 

 is formed of granite, while the east side is composed of cherty 

 dolomite and arenaceous shale. Certain schists and gneisses are 

 also classed as Cambrian, of which they represent a highly 



