[1] Ethnology, Chaps. V. and VII.
[2] See A. H. Keane, Ethnology, 1909, Chap. VII.
[3] H. Klaatsch, "Die Aurignac-Rasse und ihre Stellung im Stammbaum des Menschen," Ztschr. f. Eth. LII. 1910. See also Prähistorische Zeitschrift, Vol. I. 1909.
[4] Cf. A. Keith's criticisms in Nature, Vol. LXXXV. 1911, p. 508.
[5] W. L. H. Duckworth, Prehistoric Man, 1912, p. 146.
[6] W. Ridgeway, "The Influence of Environment on Man," Journ. Roy. Anthr. Inst., Vol. XL. 1910, p. 10.
[7] E. Dubois, "Pithecanthropus erectus, transitional form between Man and the Apes," Sci. Trans. R. Dublin Soc. 1898.
[8] O. Schoetensack, Der Unterkiefer des Homo Heidelbergensis, etc., 1908.
[9] C. Dawson and A. Smith Woodward, "On the Discovery of a Palaeolithic Skull and Mandible," etc., Quart. Journ. Geol. Soc. 1913.
[10] This was the view of A. Smith Woodward when the skull was first exhibited (loc. cit.), but in his paper, "Missing Links among Extinct Animals," Brit. Ass. Birmingham, 1913, he is inclined to regard "Piltdown man, or some close relative" as "on the direct line of descent with ourselves." For A. Keith's criticism see The Antiquity of Man, 1915, p. 503.