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^{page 447 note 1} Bucher, , op. cit., pp. 214–16.Google Scholar

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^{page 448 note 1} Hess, , op. cit., 1938, 334.Google Scholar

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^{page 449 note 1} Op. cit., 372–383.Google Scholar

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^{page 449 note 5} Op. cit., 1939.Google Scholar

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^{page 450 note 1} Kuenen, Ph. H., Quantitative estimations relating to eustatic movements, Geologie en Mijnbouw, 1939, 194–201.Google Scholar

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^{page 450 note 5} After this manuscript was ready to go to press, there appeared an article by W. H. Bucher, entitled, Deformation of the Earth's Crust (Bull. Geol. Soc. Amer., 50, 1939, 421–432). Although the groundplan of Bucher's article is entirely different from mine he reaches an analogous conclusion to the one I give in the preceding pages, viz. a pulsating rhythm in the crust of the earth. For the rest I refer the reader to his study. I applaud the fact that he has included the origin of basin-shaped structures on the continents and on the bottom of the oceans in his speculation. Up to now too little attention has been paid to these basins, which are in my opinion a characteristic just as important in the structural history of the earth as geosynclines and folded mountain-chains (see also a very recent article by H. Cloos, Hebung, Spaltung, Vulkanismus, Geol. Rundschau, 30, 4a, 1939).Google Scholar