[13] Her account is in the _American Naturalist_, 1884, p. 594, and a later synopsis in _Proceedings of the American Association for the Advancement of Science_, 1889, p. 333. [14] G. K. Gilbert, in _The American Anthropologist_, 1889, p. 173. [15] W. J. McGee, “Palæolithic Man in America,” in _Popular Science Monthly_, November 1888. [16] See G. Frederick Wright, _The Ice Age in North America_. [17] Dr. Abbott has reported his discoveries in numerous articles, and especially in his work entitled _Primitive Industry_, chapters 32, 33. [18] De Mortillet, _Le Préhistorique Antiquité de l’Homme_, p. 132, sq. [19] Mariano de la Barcena, “Fossil Man in Mexico,” in the _American Naturalist_, Aug., 1885. [20] Florentino Ameghino, _La Antiguedad del Hombre en el Plata_, passim. (2 vols, Buenos Aires, 1880.) [21] _The Descent of Man_, p. 155. Dr. Rudolph Hoernes, however, has recently argued that the discovery of such simian forms in the American tertiary as the _Anaptomorphus homunculus_, Cope, renders it probable that the anthropoid ancestor of man lived in North America. _Mittheil der Anthrop. Gesell. in Wien_, 1890, § 71. The Anaptomorphus was a lemur rather than a monkey, and had a dentition very human in character. [22] Quoted by G. F. Wright in _The Ice Age in America_, p. 583. [23] H. Habernicht, _Die Recenten Veränderungen der Erdoberfläche_, s. 27 (Gotha, 1882). He further shows that at that time both northern Russia and northern Siberia were under water, which would effectually dispose of any assumed migration by way of the latter. [24] J. W. Spencer, in the London _Geological Magazine_, 1890, p. 208, sqq. [25] James Scroll, _Climate and Time_, p. 451. [26] G. F. Wright, _The Ice Age in North America_, pp. 582-3 (New York, 1890). De Mortillet, _Le Préhistorique_, etc., pp. 186-7. H. Rink, in _Proc. of the Amer. Philos. Society_, 1885, p. 293. [27] In his excellent work, _The Building of the British Isles_, (London, 1888), Mr. A. J. Jukes-Browne presents in detail the proofs of these statements, and gives two plates (Nos. XII. and XIII.), showing the outlines of this land connection at the period referred to (pp. 252, 257, etc.). [28] Wright, _The Ice Age_, p. 504. [29] Gilbert, _Sixth An. Rep. of the Com. of the N. Y. State Reservation_, p. 84 (Albany, 1890). [30] _Races and Peoples_, chapter III. (David McKay, Philadelphia.) [31] “Palæolithic Man in America” in _Popular Science Monthly_, Nov., 1888. [32] “No one could live among the Indians of the Upper Amazon without being struck with their constitutional dislike to heat.” “The impression forced itself upon my mind that the Indian lives as a stranger or immigrant in these hot regions.” H. W. Bates, _The Naturalist on the Amazon_, Vol. II., pp. 200, 201. [33] See E. F. im Thurn, _Among the Indians of Guiana_, pp. 189, 190, who speaks strongly of the debility of the tropical Indians.