ANCIENT VOLCANIC ROCKS. 63 



(4) Bernard Hobson. An Irish Augitite. Geo/. Mag., 1892, 



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(5) A. SAUER. Erlauterungen zur Geologischen Specialkarte des 



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(7) Otto Nordenskjold. Zur Kenntniss der s.g. Halleflinten 



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(8) A. G. HOGBOM. Om postarkaiska eruptiver mom det svensk- 



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(9) N. O. HOLST. Ryoliten vid sjon Mien. Sverig. Geol. Under- 



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(12) George H. Williams. The Volcanic Rocks of South 



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 [MissJ F. BASCOM. The Structures, Origin, and Nomencla- 

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(13) George Huntington Williams. The Distribution of 



Ancient Volcanic Rocks along the Eastern Border of North 

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Alfred Harker. 



