To Abraham Dee Bartlett   30 January [1865]¹

The year is established by CD’s request for the return of the Porto Santo rabbit, which he received in February 1865 (see Variation 1: 114).

The Porto Santo rabbit was a feral form of a domesticated breed that had been introduced to Porto Santo, an island off the coast of Portugal, in the fifteenth century. It was distinct in size and colouring from the wild rabbits native to England. For CD’s interest in the rabbits, see Variation 1: 112–15, Notebooks, Notebook QE, p. 18, Correspondence vol. 5, letter from R. T. Lowe, 19 September 1854, and Correspondence vol. 6, letter from T. V. Wollaston, [February 1856]. CD had received two live rabbits from Porto Santo in 1861, and placed them at the Zoological Gardens, Regents Park, London (see Correspondence vol. 9, letter to A. D. Bartlett, 26 May [1861]). The rabbits had since undergone modifications that made them resemble the English variety in colouring (see Variation 1: 114). CD was revising the chapters on domestic animals for Variation (see ‘Journal’ (Correspondence vol. 13, Appendix II)). The material on rabbits appears in chapter 4 (Variation 1: 103–30). The Porto Santo rabbits are discussed in Variation 1: 112–15 and 2: 279.

CD had asked Bartlett to cross the Porto Santo rabbits with other breeds (Correspondence vol. 9, letter to A. D. Bartlett, 26 May [1861]). In Variation 1: 115, CD cited Bartlett’s observation that the Porto Santo rabbits would not mate with any other breed of rabbit at the Zoological Gardens. CD noted that, had the history of these rabbits not been known, most naturalists would have considered them a distinct species (see also Correspondence vol. 9, letter to P. L. Sclater, 2 June [1861]).

CD discussed Gallus sonneratii, a species of fowl, in Variation 1: 233–4, noting that he had examined the feathers of some hybrids raised at the Zoological Gardens.