skip to content

Darwin Correspondence Project

To J. S. Henslow1   [c. 26 October –] 24 November [1832]

Monte Video [Buenos Ayres]

My dear Henslow,

We arrived here on the 24th of Octob:2 after our first cruize on the coast of Patagonia: North of the Rio Negro we fell in with some little Schooners employed in sealing; to save the loss of time in surveying the intricate mass of banks, Capt: FitzRoy has hired two of them & has put officers in them.— It took us nearly a month fitting them out; as soon as this was finished we came back here, & are now preparing for a long cruize to the South.— I expect to find the wild mountainous country of Terra del. very interesting; & after the coast of Patagonia I shall thoroughily enjoy it.— I had hoped for the credit of dame Nature, no such country as this last existed; in sad reality we coasted along 240 miles of sand hillocks; I never knew before, what a horrid ugly object a sand hillock is:— The famed country of the Rio Plata in my opinion is not much better; an enormous brackish river bounded by an interminable green plain, is enough to make any naturalist groan. So hurrah for Cape Horn & the land of storms.—

Now that I have had my growl out, which is a priviledge sailors take on all occasions, I will turn the tables & give an account of my doings in Nat: History.— I must have one more growl, by ill luck the French government has sent one of its Collectors3 to the Rio Negro.—where he has been working for the last six month, & is now gone round the Horn.— So that I am very selfishly afraid he will get the cream of all the good things, before me.— As I have nobody to talk to about my luck & ill luck in collecting; I am determined to vent it all upon you.— I have been very lucky with fossil bones; I have fragments of at least 6 distinct animals; as many of them are teeth I trust, shattered & rolled as they have been, they will be recognised. I have paid all the attention, I am capable of, to their geological site, but of course it is too long a story for here.— 1st. the Tarsi & Metatarsi very perfect of a Cavia: 2nd the upper jaw & head of some very large animal, with 4 square hollow molars.—& the head greatly produced in front.— I at first thought it belonged either to the Megalonyx or Megatherium.— In confirmation, of this, in the same formation I found a large surface of the osseous polygonal plates, which “late observations” (what are they?) show belong to the Megatherium.—4 Immediately I saw them I thought they must belong to an enormous Armadillo, living species of which genus are so abundant here:5 3d The lower jaw of some large animal, which from the molar teeth, I should think belonged to the Edentata: 4th. some large molar teeth, which in some respects would seem to belong to an enormous Rodentia; 5th, also some smaller teeth belonging to the same order: &c &c.— If it interests you sufficiently to unpack them, I shall be very curious to hear something about them:— Care must be taken, in this case, not to confuse the tallies.—6 They are mingled with marine shells, which appear to me identical with what now exist.—7 But since they were deposited in their beds, several geological changes have taken place in the country.—

So much for the dead & now for the living.— there is a poor specimen of a bird, which to my unornithological eyes, appears to be a happy mixture of a lark pidgeon & snipe (Nr. 710).— Mr Mac Leay himself never imagined such an inosculating creature.—8 I suppose it will turn out to be some well-know bird although it has quite baffled me.— I have taken some interesting amphibia; a fine Bipes; a new Trigonocephalus beautifully connecting in its habits Crotalus & Viperus: & plenty of new (as far as my knowledge goes) Saurians.— As for one little toad; I hope it may be new, that it may be Christened “diabolicus”.— Milton must allude to this very individual, when he talks of “squat like [a] toad”,9 its colours are by Werner,10 ink black, Vermilion red & buff orange.— It has been a splendid cruize for me in Nat: History.— Amongst the pelagic Crustaceae, some new & curious genera.— In the Zoophites some interesting animals.— as for one Flustra, if I had not the specimen to back me up, nobody would believe in its most anomalous structure.— But as for novelty all this is nothing to a family of pelagic animals; which at first sight appear like Medusa, but are really highly organized.— I have examined them repeatedly, & certainly from their structure, it would be impossible to place them in any existing order.— Perhaps Salpa is the nearest animal; although the transparency of the body is nearly the only character they have in common.— All this may be said of another animal, although of a much simpler structure.—

I think the dried plants nearly contain all which were then Bahia Blanca flowering. All the specimens will be packed in casks—I think there will be three: (before sending this letter I will specify dates &c &c).— I am afraid you will groan or rather the floor of the Lecture room will, when the casks arrive.— Without you I should be utterly undone.— The small cask contains fish; will you open it, to see how the spirit has stood the evaporation of the Tropics.—

On board the Ship, everything goes on as well as possible, the only drawback is the fearful length of time between this & day of our return.— I do not see any limits to it: one year is nearly completed & the second will be so before we even leave the East coast of S America.— And then our voyage may be said really to have commenced.— I know not, how I shall be able to endure it.— The frequency with which I think of all the happy hours I have spent at Shrewsbury & Cambridge, is rather ominous.— I trust everything to time & fate & will feel my way as I go on:— We have been at Buenos Ayres for a week.— Novr. 24th.— It is a fine large city; but such a country; everything is mud; You can go no where, you can do nothing for mud.— In the city I obtained much information about the banks of the Uruguay.— I hear of Limestone with shells, & beds of shells in every direction.— I hope, when we winter in the Plata to have a most interesting Geological excursion in that country.— I purchased fragments (Nors: 837 & 8) of some enormous bones; which I was assured belonged to the former giants!!— I also procured some seeds.— I do not know whether they are worth your accepting; if you think so, I will get some more:— They are in the box: I have sent to you by the Duke of York Packet, commanded by Lieu: Snell to Falmouth.— two large casks, containing fossil bones.—a small cask with fish, & a box containing skins, spirit bottle &c & pill-boxes with beetles.— Would you be kind enough to open these latter, as they are apt to bec⁠⟨⁠ome⁠⟩⁠ mouldy.— With the exceptions of the bones, the rest of my collection looks very scanty. Recollect how great a proportion of time is spent at sea. I am always anxious to hear in what state my things come & any criticisms about quantity or kind of specimens.— In the smaller cask is part of a large head, the anterior portions of which are in the other large ones.— The packet has arrived & I am in a great bustle: You will not hear from me for some months:

Till then believe me, my dear Henslow, Yours very truly obliged, Chas Darwin.—

Remember me most kindly to Mrs. Henslow.—


The following passages from this letter were extracted by Henslow and published in the Cambridge Philosophical Society pamphlet: 1.1 ‘We arrived … Rio Negro’ 1.2 1.8 ‘I had hoped … groan.’ 1.14 2.8 ‘I have been … &c &c.’ 2.22 2.24 ‘They … country.’ 2.27 3.1 ‘there … creature.’ 3.4 3.5 ‘I have taken … toad’ 3.10 3.11 ‘Amongst … common.’ 3.19 5.8 ‘We have been … direction.’ 5.12 5.13 ‘I purchased … giants!!’ 5.15
According to ‘Beagle’ diary and Robert FitzRoy’s meteorological log, the Beagle was still at sea on 24 and 25 October. The earliest they might have arrived at Montevideo was late on the 25th.
Alcide Charles Victor Dessalines d’Orbigny. From 1826 to 1833 he travelled throughout South America, collecting specimens for the Muséum d’Histoire Naturelle. He published the results in Orbigny 1835–47.
Described in Fossil Mammalia, pp. 63–73, by Richard Owen, who identified it as belonging to a distinct subgenus of Megatheroid Edentata, to which he gave the name Mylodon darwinii. The ‘late observations’ refer to English newspaper accounts of the Megatherium fossil found by Sir Woodbine Parish in 1831 (see letter to J. S. Henslow, 11 April 1833, n. 7).
After the voyage, in discussing the origin of his evolutionary views, CD frequently cited the relationship of living species like the armadillo to South American fossils as important in suggesting the possibility of transmutation (e.g., ‘Journal’, Appendix I, entry for 1837; Autobiography, pp. 118–19). Some of these references have led to the view that CD arrived at the hypothesis during the voyage. Most scholars, however, now hold that the ‘conversion’ to evolution came after CD had returned to London. See Sulloway 1982b for a discussion of the various views. Sulloway makes a convincing case that CD saw the evolutionary significance of his collections only after his ornithological and fossil specimens had been classified by John Gould and Richard Owen.
The tallies were tags with numbers corresponding to those in his catalogues of specimens.
Orbigny named twenty species of shells, all of living species, collected by CD from the Punta Alta formations (see South America, p. 83).
William Sharp Macleay. In his Horæ entomologicæ (Macleay 1819–21), he propounded the Quinary System of classification in which the five main animal groups are represented by ‘circles of affinity’. To represent the continuity of forms the circles are arranged in a larger circle in which each is contiguous or ‘inosculant’ with two others. Loren Eiseley cited CD’s use of ‘inosculating’ as evidence of an early, unacknowledged debt to Edward Blyth, but Macleay’s system and its vocabulary were well known to CD long before he knew of Blyth. See Eiseley 1959 and S. Smith 1968. The inosculating bird is identified as Tinochorus rumicivorus in Birds, pp. 117–18.
Paradise lost 4. 799–800. CD had a copy of Milton’s poems with him on the voyage.


Autobiography: The autobiography of Charles Darwin 1809–1882. With original omissions restored. Edited with appendix and notes by Nora Barlow. London: Collins. 1958.

‘Beagle’ diary: Charles Darwin’s Beagle diary. Edited by Richard Darwin Keynes. Cambridge: Cambridge University Press. 1988.

Birds: Pt 3 of The zoology of the voyage of H.M.S. Beagle. By John Gould. Edited and superintended by Charles Darwin. London: Smith, Elder and Co. 1839–41.

Fossil Mammalia: Pt 1 of The zoology of the voyage of H.M.S. Beagle … during the years 1831 to 1836. By Richard Owen. Edited and superintended by Charles Darwin. London: Smith, Elder and Co. 1839–43.

Macleay, William Sharp. 1819–21. Horæ entomologicæ: or essays on the annulose animals. 2 pts. London: S. Bagster.

Orbigny, Alcide Charles Victor Dessalines d’. 1835–47. Voyage dans l’Amérique Méridionale (le Brésil, la République orientale de l’Uruguay, la République Argentine, la Patagonie, la République du Chili, la République de Bolivia, la République du Pérou), exécuté pendant les années 1826 … 1833. 6 vols. in 7 and 4 atlases. Paris and Strasbourg: Pitois-Levrault et Cie, P. Bertrand.

Smith, Sydney. 1968. The Darwin collection at Cambridge with one example of its use: Charles Darwin and Cirripedes. Actes du XIe Congrès International d’Histoire des Sciences 5: 96-100.

South America: Geological observations on South America. Being the third part of the geology of the voyage of the Beagle, under the command of Capt. FitzRoy RN, during the years 1832 to 1836. By Charles Darwin. London: Smith, Elder & Co. 1846.

Syme, Patrick. 1821. Werner’s nomenclature of colours, with additions, arranged so as to render it highly useful to the arts and sciences, particularly zoology, botany, chemistry, mineralogy, and morbid anatomy. Annexed to which are examples selected from well-known objects in the animal, vegetable, and mineral kingdoms. 2d ed. Edinburgh.


A French collector [Alcide d’Orbigny] has been at the Rio Negro and will probably have "taken the cream". CD’s luck with fossil bones, among them a large extinct armadillo-like animal. Describes some birds, toads, Crustacea, and other marine specimens. Nearly all plants flowering at Bahia Blanca were collected. Is sending two large casks of fossil bones by packet.

Letter details

Letter no.
Charles Robert Darwin
John Stevens Henslow
Sent from
Source of text
Royal Botanic Gardens, Kew (Henslow letters: 14 DAR/1/1/14)
Physical description
ALS 4pp †

Please cite as

Darwin Correspondence Project, “Letter no. 192,” accessed on 18 May 2024,

Also published in The Correspondence of Charles Darwin, vol. 1