[541] Quoted by Hertwig. See also K. Goebel, "Die Grundprobleme der heutigen Pflanzenmorphologie," Biol. Centrbl., xxv., pp. 65-83, 1905.
[542] This is also emphasised by Fleischmann in his critical study of evolutionary morphology entitled Die Descendenztheorie, Leipzig, 1901.
[543] The same remark applies to the bulk of speculation as to the factors of evolution, with the exception of the contributions made to evolution theory by the palæontologists by profession, such as Cope.
[544] Les Transformations du Monde animal, Paris, 1907.
[545] "Malacology versus Palæoconchology," Proc. Malacological Soc., viii., pp. 66-83, 1908.
[546] Particularly by E. Perrier, "La Tachygenèse," Ann. Sci. nat. (Zool.) (8), xvi., 1903.
[547] Monatsber. k. Akad. Wiss., Berlin, pp. 474-504, 1866.
[548] Geognost. u. Palæont. Beiträge, ii., Heft 2, pp. 181-256, 1869.
[549] Abhand. k.k. Geol. Reichsanstalt, vii., Wien, 1875.
[550] The case for polyphyletism is very strongly put by G. Steinmann in his book, Die geologischen Grundlagen der Abstammungslehre, Leipzig, 1908.