Part 3

HOLMES, A.—The Age of the Earth. Harper and Bros., London and New York, 1913.

JOLY, J.—Radioactivity and Geology. Van Nostrand, N. Y., 1909;

An Estimate of the Geological Age of the Earth. Trans. Roy. Soc. Dublin, VII. 1899, pp. 23-66;

The Age of the Earth. Phil. Mag., 6th ser., Vol. XXII, 1911, pp. 359-80.

SOLLAS, W. J.—Presidential Address. Quart. Journ. Geol. Soc., Vol. 65, 1909, pp. cxii; Proc. Geol. Soc. of London, Sess. 1908-9, pp. i-cxxii.

WALCOTT, C. D.—Geologic Time, as indicated by the sedimentary rocks of North America. Smithsonian Rep. 1893, pp. 301-334; Jour. Geol. Vol. III, 1893, pp. 639-674.

EVOLUTION OF FISH TO MAMMAL-LIKE REPTILE.

1, FISH. 2, AMPHIBIAN. 3, REPTILE. 4, MAMMAL-LIKE REPTILE.

(Figs. 1, 2, after Klaatsch, 3, based on Williston, 4, based on Gregory).

Drawings by Sharat K. Roy.]

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