Weismann's The Evolution Theory, translated by J.A. and Margaret Thomson, 2 vols., 1904, contains the best statement of Weismann's views. It is remarkably clear in its exposition of a complicated theory. The Germ-Plasm, 1893; Romanes's An Examination of Weismannism, 1893. Inheritance of Acquired Characters: Weismann's discussion, _loc. cit._, vol. II, very good. Romanes's Darwin and After Darwin, vol. II. Personality of Weismann: Sketch and brief autobiography, in _The Lamp_, vol. 26, 1903, portrait; Solomonsen, Bericht über die Feier des 70 Geburtstages von August Weismann, 1905, 2 portraits. Mutation-Theory of De Vries: Die Mutations-Theorie, 1901; Species and Varieties, their Origin by Mutation, 1905; Morgan, Evolution and Adaptation, 1903, gives a good statement of the Mutation Theory, which is favored by the author; Whitman, The Problem of the Origin of Species, _Congress of Arts and Science, Universal Exposition, St. Louis_, 1904; Davenport, Evolution without Mutation, _Journ. Exp. Zool._, April, 1905. CHAPTER XIX For early phases of Evolutionary thought consult Osborn, From the Greeks to Darwin, 1894, and Clodd, Pioneers of Evolution, 1897. Suarez and the Doctrine of Special Creation: Huxley, in Mr. Darwin's Critics, _Cont. Rev._, p. 187, reprinted in Critiques and Addresses, 1873. Buffon: In Packard's Life of Lamarck, chapter 13. E. Darwin: Krause's Life of E. Darwin translated into English, 1879; Packard, _loc. cit._ Goethe: Die Idee der Pflanzenmetamorphose bei Wolff und bei Goethe, Kirchoff, 1867; Goethe's Die Metamorphose der Pflanzen, 1790. Oken: His Elements of Physiophilosophy, Ray Soc., 1847. Cuvier and St. Hilaire: Perrier, La Philosophie Zoologique avant Darwin, 1884; Osborn, _loc. cit._ Darwin and Wallace: The original communications of Darwin and Wallace, with a letter of transmissal signed by Hooker and Lyell, published in the _Trans. Linnæan Soc._ for 1858, were reprinted in the _Pop. Sci. Mo._, vol. 60, 1901. Darwin: Personality and biography (For references to his theory see under Chapter XVII); Life and letters by his son, 3 vols., 1887, new ed., 1896; More Letters of Charles Darwin, 2 vols., 1903; Chapter in Marshall's Lectures on the Darwinian Theory; Darwin, Naturalist's Voyage around the World, 1880; Gould, Biographical Clinics, for Darwin's illness due to eye-strain; Poulton, Chas. Darwin and the Theory of Natural Selection, 1896. Wallace: My Life, 2 vols., 1905; The Critic, Oct., 1905. Huxley: Life and Letters by his son, 1901; Numerous sketches at the time of his death, 1895, in _Nature_, _Nineteenth Century_, _Pop. Sci. Mo._, etc., etc. Haeckel: His Life and Work by Bölsche, 1906. CHAPTER XX