To P. L. Sclater   21 [April 1861]

Down Bromley Kent

21.

Dear Sclater

As you are working at Birds of S. America,1 & for my credit sake do oblige me & look at Birds in Zoolog. of Beagle p. 67 & see what I say on the 3 species of Opetiorhynchus & consider whether I am likely to have blundered when I observed difference of Habits of the species;2 so at p. 74 on Scytalopus, when I specify difference of habits.3 I see that I have made a horrid mistake in speaking of O. parvulus, which was a name temporarily attached, I believe, to one of the forms of O. Patagonicus.4 I believe that Capt. Abbot must have confounded O. vulgaris & antarcticus,5 which, as I remarked on the spot, are most closely similar except in habits.—

I much enjoyed my talk with you.—6 This note obviously requires no answer & written chiefly to indicate my self-conceit—

Yours very truly | C. Darwin

The Opetiorhynchus from Chiloe seems case of intermediate variety7

Endorsement: ‘April 1861’

1
Sclater may have informed CD that he was working on a catalogue of his collection of American birds (Sclater 1862). This volume served to bring together much of the information Sclater supplied in his many papers on birds of American origin, including that on the birds of the Falkland Islands (Sclater 1860–1). See n. 5, below.
2
Birds constituted part three of The zoology of the voyage of H.M.S. Beagle. Species descriptions were provided by John Gould; CD gave information concerning habits and habitats. The reference is to Opetiorhynchus patagonicus (a synonym of Cinclodes patagonicus, the dark-bellied cinclodes) (Tierra del Fuego), O. antarcticus (a synonym of Cinclodes antarcticus, the blackish cinclodes) (Falklands), and O. nigrofumosus (a synonym of Cinclodes nigrofumosus, the Chilean seaside cinclodes) (Northern Chile).
3
In Birds, p. 74, CD described and compared Scytalopus magellanicus (the Andean tapaculo) and S. fuscus (the dusky tapaculo).
4
In Birds, p. 67, CD discussed the differences between O. parvulus and O. vulgaris as though O. parvulus was a species in its own right rather than a variety of O. patagonicus.
5
In Abbot 1861, p. 154, Charles Compton Abbott claimed to have seen only one species of the genus Cinclodes (Opetiorhynchus), C. antarcticus, on the Falkland Islands. In Sclater 1860–1, p. 385, Sclater noted both C. vulgaris and C. antarcticus as being natives of the Falkland Islands.
6
CD was in London from 16 to 20 April 1861 (Emma Darwin’s diary). It is possible that CD met Sclater at a meeting of the Linnean Society of London that he attended.
7
In Birds, p. 67, CD described a long-beaked variety of O. patagonicus that inhabited the island of Chiloe.

Manuscript Alterations and Comments

1.8 antarcticus] after del ‘Patagoni’
4.1 seems] underlining in pencil

Please cite as “DCP-LETT-3123,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-3123