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elusion is reached that the schists to the southwest are Lower 

 Huronian, and that the intruding granites are post-Lower 

 Huronian. If this conclusion be correct, the granites and schists 

 of the central and eastern portions of Minnesota must be mapped 

 as Algonkian rather than Archean, as in the past. 



Ami 'briefly summarizes the salient features of the geology 

 of the principal cities of eastern Canada, including St. John, 

 Ottawa, Quebec, Montreal, and Toronto. 



Ami 2 summarizes the geology of Canada, and indicates the 

 meaning and correlation of the principal terms employed in 

 Canadian geological nomenclature. 



Ells 3 sketches the development of geological work in the 

 province of Quebec. 



Ells 4 describes and maps the geology of the Three Rivers 

 sheet of the "Eastern Townships" map, Province of Quebec. 

 Archean rocks occupy most of the northwestern portion of the 

 area north of the St. Lawrence River. A portion of this area, 

 including anorthosite masses, has previously been described by 

 Adams. 5 



The great mass of the rocks seen pertain to the Grenville series, 

 rather than to the so-called " Fundamental "gneiss. The composi- 

 tion of the Grenville series, with its crystalline limestones and 

 with rusty gneiss bands, very closely resembles that met with in 

 the lower Ottawa district, but the calcareous members are much 

 less widely developed. There are also large areas of anortho- 

 site, red granite, augen-gneiss and masses of green pyroxenic 

 diabase. Quartzite is an important component of this series, 

 and large areas of this rock, similar to that found along the 



111 On the Geology of the Principal Cities of Eastern Canada," by Henry M. 

 Ami, Trans. RoyalSoc. of Canada, Vol. VI, 1900; sec. iv, pp. 125-64. 



2 "Synopsis of the Geology of Canada," by Henry M. Ami, Trans. Royal Soc. 

 of Canada, Vol. VI, 1900, sec. iv, pp. 187-225. 



^ "Problems in Quebec Geology," by Robert W. Ells, Record of Science, Vol. 

 VII, 1898, pp. 480-502. 



4 Geol. Surv. of Canada, Annual Report, New Series, Vol. XI, for 1898, pp. 5 J-70 

 J; with geological map. 



s Geol. Surv. of Canada, Vol. VIII, Part J. Summarized, Jour. Geol., Vol. VII, 

 p. 401. 



