1. Robby Kossmann, “Die Bedeutung des Einzellebens in der Darwinistischen Weltanschauung,” Nord und Süd 12 (1880): 420–1.
2. Marx to Engels, December 19, 1860, in Marx-Engels Werke (Berlin, 1959 ff), XXX: 131. For more on the socialist reception of Darwinism in Germany, see Richard Weikart, Socialist Darwinism (San Francisco, 1999); Kelly, Descent of Darwin, ch. 7; Ted Benton, “Social Darwinism and Socialist Darwinism in Germany: 1860 to 1900,” Rivista di filosofia 73 (1982): 79–121
3. Kurt Bayertz, “Naturwissenschaft und Sozialismus. Tendenzen der Naturwissenschaft-Rezeption in der deutschen Arbeiterbewegung des 19. Jahrhundert,” Social Studies of Science 13 (1983): 355–94
4. Renate Bridenthal et al., eds., When Biology Became Destiny: Women in Weimar and Nazi Germany (New York: Monthly Review Press, 1984).
5. Many scholars discuss the complex issue of Nazism and modernity, but see especially Michael Burleigh and Wolfgang Wippermann, The Racial State: Germany, 1933–1945 (Cambridge, 1991); Norbert Frei, “Wie modern war der Nationalsozialismus,” Geschichte und Gesellschaft 19 (1993): 367–87