[103] As confirming this analysis of evolution, reference is made to Mach: "Die Mechanik in ihrer Entwicklungen," p. 128, and "Beitrage zur Analyse der Empfindungen," pp. 25, 154; also Avenarius: "Kritik der reinen Erfahrung."

[104] See above essay by Petzoldt.

[105] "Die Entwicklungsgeschichte des Weltalls," 1882.

[106] "Gestaltungen des Zweckmässigen."

[107] "Die Entwicklungsgeschichte des Weltalls," chap. I.

[108] See especially Darwin: "The Variation of Animals and Plants under Domestication"; Haeckel: "Natürliche Schöpfungsgeschichte," 8th ed., 1889, p. 179 et seq.

[109] "Die Entstehung der Arten auf Grund von Vererben erworbener Eigenschaften," p. 204 et seq.

[110] Ibid. p. 190 et seq.

[111] "Entstehung der Arten," p. 15.