DARWINISM AND EVOLUTION DEFINED. 23 



Edw., "Pioneers of Evolution from Thales to Huxley," 1897; 

 and Quatrefages, A. de, "Les fimules de Darwin," 2 vols., 1894. 



8 Many of the hermit crabs (Paguridae) which live in the dis- 

 carded shells of gasteropod molluscs have some species of small 

 colonial polyp, as Podocoryne, attached to and partly covering the 

 shell. The polyp colony profits by being carried about and by obtain- 

 ing bits of food when the crab has succeeded in catching prey and 

 is tearing it to pieces with his claws, while the crab profits by the 

 protection afforded it by the stinging threads and nettle cells of 

 the polyp. Esig saw in the aquaria of the zoological station at 

 Naples a small octopus which was trying to insert one of its ten- 

 tacles into a shell to get the crab, quickly driven away by the many 

 stinging threads with which it was caressed by the polyp colony 

 seated on the outer surface of the shell. This symbiotic life between 

 hermit crab and polyp goes so far with some species that the hermit 

 crabs never rest until they have a polyp colony seated on their shell. 



4 Among more recent books stating the essential points in this 

 evidence may be mentioned Conn's "Evolution of To-day," 1889; 



Books giving Wallace's "Darwinism," 1891 ; A. M. Marshall's 

 the evidences for "Lectures on the Darwinian Theory," 1894; Ro- 

 descent. manes's "Darwin and After Darwin," Vol. I, 1896; 



Klaatsch's "Grundziige der Lehre Darwins," 1900; Metcalf's "Out- 

 line of the Theory of Organic Evolution," 1904; Weismann's 

 "Vortrage iiber Descendenztheorie," 2 vols., 1902; Eng. trans. 2 

 vols., 1904; Lotsy, J. P., "Vorlesungen iiber Descendenztheorien, 

 mit besonderer Beriicksichtigung der botanischen Seite der Frage," 

 2 vols., Vol. I, 1906; Jordan and Kellogg, "Evolution and Animal 

 Life." 1907. 



5 For an interesting discussion from the modern point of view of 

 the relation between Darwinian biology and theology see Haeckel, 



Discussions of Ernst ' " Der Monismus als Band zwischen Religion 

 relation of de- und Wissenschaft," 1893; also Vetter, Benjamin, 

 scent and the- "Die moderne Weltanschauung und der Mensch," 

 olo gy- 1903; also Wasmann, Erich, "Die moderne Biologic 



und die Entwicklungstheorie," 1904. (Author is a Jesuit priest whose 

 remarkable studies on ants and their messmates have made him well 

 known to biologists. He accepts the theory of descent, with the ex- 

 clusion of man from the evolution series.) See also Hutton, F. W., 

 "The Lesson of Evolution," 1902. In this book the author takes a 

 strong stand for dualism, making the point that the theory of evo- 

 lution has rescued philosophy from a rigidly monistic materialistic 

 basis (a mind-in-all-matter theory), and has made necessary a dual- 

 istic theory (mind-and-matter theory) because of the necessity of 

 postulating the beginning of life and a beginning of mind. The 



