General: Romanes, Darwin and After Darwin, 1892, vol. I, chaps. I-V; Same author, The Scientific Evidences of Organic Evolution; Weismann, Introduction to the Evolution Theory, 1904; Osborn, Alte und Neue Probleme der Phylogenese, _Ergebnisse der Anat. u. Entwickel._, vol. III, 1893; Ziegler, Ueber den derzeitigen Stand der Descendenzlehre in der Zoologie, 1902; Jordan and Kellogg, Evolution and Animal Life, 1907, chaps. I and XIV. Evolutionary Series--Shells: Romanes, _loc. cit._; Hyatt, Transformations of Planorbis at Steinheim, _Proc. Am. Ass. Adv. Sci._, vol. 29, 1880. Horse: Lucas, The Ancestry of the Horse, _McClure's Mag._, Oct., 1900; Huxley, Three Lectures on Evolution, in Amer. Addresses. Embryology--Recapitulation Theory: Marshall, Biolog. Lectures and Addresses, 1897; Vertebrate Embryology, 1892; Haeckel, Evolution of Man, 1892. Primitive Man: Osborn, Discovery of a Supposed Primitive Race of Men in Nebraska, _Century Mag._, Jan., 1907; Haeckel, The Last Link, 1898. Huxley, Man's Place in Nature, collected essays, 1900; published in many forms. Romanes, Mental Evolution in Man and Animals. CHAPTER XVII Lamarck: Packard, Lamarck, the Founder of Evolution, His Life and Work, with Translations of his Writings on Organic Evolution, 1901; Lamarck's Philosophie Zoologique, 1809. Recherches sur l'Organisation des corps vivans, 1802, contains an early, not however the first statement of Lamarck's views. For the first published account of Lamarck's theory see the introduction to his Système des Animaux sans Vertèbres, 1801. Neo-Lamarckism: Packard, _loc. cit._; also in the Introduction to the Standard Natural History, 1885; Spencer, The Principles of Biology, 1866--based on the Lamarckian principle. Cope, The Origin of Genera, 1866; Origin of the Fittest, 1887; Primary Factors of Organic Evolution, 1896, the latter a very notable book. Hyatt, Jurassic Ammonites, _Proced. Bost. Sci. Nat. Hist._, 1874. Osborn, _Trans. Am. Phil. Soc._, vol. 16, 1890. Eigenmann, The Eyes of the Blind Vertebrates of North America, _Archiv f. Entwicklungsmechanik_, vol. 8, 1899. Darwin's Theory (For biographical references to Darwin see below under Chapter XIX): Wallace, Darwinism, 1889; Romanes, Darwin and After Darwin, vol. I, 1892; Metcalf, An Outline of the Theory of Organic Evolution, 1904, good for illustrations. Color: Poulton, The Colors of Animals; Chapters in Weismann's The Evolution Theory, 1904. Mimicry: Weismann, _loc. cit._ Sexual Selection: Darwin, The Descent of Man, new ed., 1892. Inadequacy of Nat. Selection: Spencer, The Inadequacy of Natural Selection, 1893; Morgan, Evolution and Adaptation, 1903. Kellogg, Darwinism To-day, 1907, contains a good account of criticisms against Darwinism. CHAPTER XVIII