To P. L. Sclater   4 February [1860]1

Down Bromley Kent

Feb 4th

My dear Sir

I thank you extremely for your list of the Galapagos Birds, & I trust that it will be in time for a note at end of my Journal, & will likewise do to correct the Origin of Species.—2

The wren is Sylvicola aureola figured in Zoology of Beagle;3 I have assumed that it confined to the Archipelago. I am surprised that the Zenaida “probably occurs on Mainland”.—4

Do you remember my asking you to be so very kind as to keep in mind & make memorandum for me of any cases of abnormal parts in Birds being variable. Will you kindly run your eye through enclosed list5 (& after having looked through it, tear it up) & then you will see the sort of cases, which interest me, & very grateful I shall be for any assistance on this head.—

With my best thanks for your kind assistance | Believe me | Yours sincerely | C. Darwin

1
Dated by the publication in 1860 of a new issue of Journal of researches that included Sclater’s information.
2
See letter from P. L. Sclater, [3? February 1860]. CD cited Sclater’s information concerning the Galápagos birds in Journal of researches (1860), p. vii. The first edition of Origin (p. 389) refers to twenty-five of the twenty-six land birds being ranked as distinct species. CD corrected the relevant passage in Origin 3d ed., p. 429: There are twenty-six land-birds, and twenty-one, or, perhaps, twenty-three, of these are ranked as distinct species, and are supposed to have been created here; yet the close affinity of most of these birds to American species in every character, in their habits, gestures, and tones of voice, was manifest.
3
See the letter from P. L. Sclater, [3? February 1860] for Sclater’s query about this species. CD refers to Birds, p. 86. Sylvicola aureola is a synonym of Setophaga petechia subsp. aureola, the mangrove warbler.
4
Zenaida galapagoensis was described in Birds, p. 115, as a bird that was confined to the Galápagos Archipelago. In Journal of researches (1860), p. vii, CD instead included it among the Galápagos birds that were also found on the mainland. Recent authorities state that Z. galapagoensis is endemic to the islands (Harris 1974, p. 119).
5
The list has not been found. The variability of abnormally developed structures had particularly engaged CD in 1857 while he was writing the chapter on ‘Laws of variation: varieties and species compared’ for his species book (see Natural selection, pp. 309–11, and Correspondence vol. 6, letter to J. D. Hooker, 16 [May 1857]).

Manuscript Alterations and Comments

1.2 my Journal] above del ‘Book’

Please cite as “DCP-LETT-2684,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-2684