Chapter I: The Observer

[1] _Journal des Goncourts_, May 1, 1857, vol. I, p. 182.

[2] Ben Jonson, _The Poetaster_, act II, scene 1.

[3] _Sentimental Journey_, ‘In the Street.’

[4] _Portraits Littéraires_, vol. III, p. 546.

[5] _Expression_, p. 80.

[6] Thoreau, _Journal_, vol. VII, p. 46.

[7] Gray, to Darwin, May 18, 1862, Gray, _Letters_, vol. II, p. 481.

[8] _Great Naturalists_, p. 51.

[9] _More Letters_, vol. I, p. 72.

[10] _Life_, vol. I, p. 83.

[11] To Farrar, November 26, 1868, _Life_, vol. II, p. 453.

[12] To Hooker, 1867, _More Letters_, vol. II, p. 6.

[13] To Lyell, June 1, 1867, _Life_, vol. II, p. 248.

[14] To Wilson, April 29, 1878, _More Letters_, vol. II, p. 421.

[15] To Galton, November, 1879, _Life_, vol. II, p. 414.

[16] To Lyell, March 17, 1863, _Life_, vol. II, p. 201.

[17] To Galton, November 8, 1872, _More Letters_, vol. II, p. 108.

[18] _Expression_, p. 184.

[19] To Dr. Ogle, March 12, 1871, _Life_, vol. II, p. 321.

[20] _More Letters_, vol. I, p. 4.

[21] To Jenyns, October 17, 1846, _Life_, vol. I, p. 396.

[22] _Beagle Journal_, p. 282.

[23] To Gray, June 3, 1874, _Life_, vol. II, p. 457.

[24] To Hooker, December 11, 1860, _Life_, vol. II, p. 148.

[25] To Scott, July 2, 1863, _More Letters_, vol. II, p. 323.

[26] To Horner, January, 1847, _More Letters_, vol. II, p. 224.

[27] _Expression_, p. 12.

[28] _Life_, vol. II, p. 238.

[29] _More Letters_, vol. II, p. 105.

[30] _Life_, vol. I, p. 40.

[31] _Different Forms of Flowers_, p. 189.

[32] To Wiesner, October 4, 1881, _More Letters_, vol. II, p. 432.

[33] _Life_, vol. I, p. 124.

[34] _Ibid._

[35] _Life_, vol. I, p. 125.

[36] _Life_, vol. II, p. 453.

[37] _Cirripedia_, p. 155.

[38] To Lyell, September 12, 1860, _Life_, vol. II, p. 133.

[39] _Darwiniana_, p. 275.

[40] To Hooker, February 4, 1861, _Life_, vol. II, p. 153.

[41] To Lyell, March 9, 1850, _More Letters_, vol. II, p. 229.

[42] _Life_, vol. I, p. 125.

[43] _Life_, vol. I, p. 105.

[44] _Life_, vol. I, p. 80.

[45] _Life_, vol. I, p. 121.

[46] _Purgatorio_, canto III.

[47] To Miss S. Darwin, August 4, 1836, _Life_, vol. I, p. 237.

[48] To Hooker, 1847, _Life_, vol. I, p. 317.

[49] _More Letters_, vol. I, p. 3.

[50] To Miss C. Darwin, November 8, 1834, _Life_, vol. I, p. 230.

[51] _Beagle Journal_, p. 78.

[52] _Life_, vol. I, p. 109.

[53] _Expression_, p. 194.

[54] To Romanes, May 29, 1876, _More Letters_, vol. I, p. 364.

[55] To Fox, May, 1832, _Life_, vol. I, p. 206.

[56] To Henslow, May 18, 1832, _Life_, vol. I, p. 208.

[57] To Henslow, August 15, 1832, _More Letters_, vol. I, p. 9.

[58] _Journal_, August 29, 1858, vol. XI, p. 137.

[59] _Journal_, December 4, 1856, vol. IX, p. 158.

[60] _Life_, vol. I, p. 368.

[61] _Worms_, p. 97.

[62] _Origin_, p. 105.

[63] In _Popular Science Monthly_, April, 1909, vol. LXXIV, p. 198.