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[225] H. Helmolt, History of the World, Vol. III, pp. 400, 417, New
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[226] A.C. Haddon, The Study of Man, p. xix. New York and London, 1898.

[227] James Bryce, Migrations of the Races of Men Considered
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[228] Eleventh Census, _Report on the Indians_, pp. 34-35. Washington,
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[229] H. Helmolt, History of the World, Vol. III, p. 42. New York,
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[230] Ratzel, History of Mankind, Vol. II, pp. 279-283, London, 1896-98.

[231] Jerome Dowd, The Negro Races, Vol. I, pp. 47-48, 61-62. New York,
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[232] Sweden, Its People and Its Industries, p. 93. Edited by G.
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[233] Sir John Lubbock, Prehistoric Times, pp. 589-593. New York, 1872.

[234] G.P. Marsh, The Earth as Modified by Human Action, New York, 1877.

[235] W.Z. Ripley, Races of Europe, pp. 261-267. New York, 1899.