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Darwin Correspondence Project

From George Bentham   [before 22 April 1868]1

25, Wilton Place, | S.W.

⁠⟨⁠  ⁠⟩⁠

My dear Mr Darwin

At odd times that I have been able to spare from the systematic work that presses upon me the study of your Variation of Plants and Animals has been of the greatest interest—2 Whilst I cannot perhaps quite follow you as yet as to reversion and pangenesis in which there is so much that seems beyond our powers of conception I am amazed at the mass of observations you have made collected and methodised in relation to the portion of your subject now illustrated and can only hope that I may live to see and study the promised remainder.3 In the meantime there are two or three very small matters I have noted as I went on w⁠⟨⁠hich I⁠⟩⁠ th⁠⟨⁠ough⁠⟩⁠t might possibly interest y⁠⟨⁠ou. On⁠⟩⁠ that chance I send them as you can easily throw this into the fire.

First as to Asses you have mentioned once or twice their little variation owing to their being of little value and bred by poor people, and v. ii. 236, 237 you mention some exceptions. I think very striking exceptions may be found in those few Mediterranean countries where larger races are valued for riding but especially in those parts of Poitou Perigord and Limousin4 where mules are or at least were extensively bred for the Spanish market. I remember when residing at Saumur5 in 1814–15 the great variety of asses from Poitou which occasionally appeared at a great fair some 8 or 10 miles south of Saumur, especially a ferocious long-haired breed much used for stallions. I have no new book on the subject but in Herbin’s Statistique 1807 I find these asses called Mirebalais or in the country Animaux bourraquets or baudets (the latter the name we knew them by) thus described.6 “Leur taille ordinaire est de 1 mètre 40 à 50 centîms (4 pieds 3 à 6 pouces) et on en trouve de 1 mètre 67 centimètres (5 pieds)*… Ils sont très-étoffés; leurs jambes sont presque aussi fortes que celles des chevaux de carrosse, leur poil est long de 16 à 17 centimètres (6 pouces), la dimension de leur cornes (hoofs) est double de celle-ci. Ils passent pour très-vicieux et féroces, sont attachés avec des chaînes de fer, peuvent servir jusqu’à cent jumens dans le temps de la monte, durent plus de vingt ans et finissent de vieillesse. Les plus estimés sont ceux dont le poil est très-noir”. Sonnini in Detervilles Dictionnaire d’Histoire Naturelle a few years earlier gives nearly the same details and adds7 “On ne les emploie que pour étalons et comme on ne les ferre jamais leur corne s’allonge d’une manière désagréable … on les vend fort cher, suivant leur taille, et surtout d’après la largeur et l’épaisseur de leurs jarrets, il s’en est vendu cinq cents écus et même jusqu’à trois et quatre mille livres la pièce; les noirs sont les a plus estimés.” The race is said (in 1807) to have much diminished. I know not whether it still exists. I have not been staying in that part of the country since 1815 and the race is unknown in other parts of France. In general the agricultural industry of the central and west central parts of France has very much gone down from the effects of centralisation.

Phaseolus vulgaris8 appears to me to be an excellent instance of variability in selected characters. In the same west central provinces of France where I believe agricultural industry was relatively much more advanced before the great revolution than it is now the ripe seeds formed a very important item in the food of the peasantry of the bourgeoisie and even of the better families in the provincial towns and were broad in great abundance to the corn-markets in sacks like the corn in numerous distinct varieties selected by the distinct customers the large flat white haricôts de Soissons9 for the table of the rich the common medium sized mottled or brown very productive kinds for the common food of the peasantry, the narrow-oblong reddish brown kind sought after by some, and the rarer small round haricot-riz look so different that Savi whose monograph was followed by De Candolle distinguished them all as species—10 Again they have all dwarf and erect and tall twining varieties and yet all or nearly all must be varieties produced by cultivation in Europe which is certainly not the native land of the species. In Asia which is much more probably its origin I have never been able to discover that the varieties are near so numerous or so marked. In all these very marked variations in seed and stature—the two useful properties—“there is a remarkable sameness in the neglected characters of foliage inflorescence flowers and especially in the bracteoles—an insignificant character in the eyes even of botanists but by which and by which alone as far as we know the species can always be distinguished from all others, wild or cultivated”.11 I have never seen certainly wild specimens of Phaseolus vulgaris but curiously enough an expedition that was sent two or three years since to try to find a place for settlement on the N. W. coast of Australia about Nichol Bay12 amongst a set of the plants they gathered during their short stay sent home young specimens of Phaseolus vulgaris— The scarlet runner a Mexican plant of recent cultivation and little known on the Continent except as an ornamental plant has not varied much but our growers have already obtained a dwarf erect variety”.13 Other species of Phaseolus and Vigna14 much cultivated in warm countries vary considerably but I believe none in the seed to anything like the degree that P. vulgaris does in those European countries where it has long been intelligently cultivated as an important article of food.

I cannot say I am at all convinced I was wrong in my conviction that the wheats cultivated (common wheat, Spelt and T. monococcum) are derived from species of Ægylops—probably from three different species. I think De Candolles statement of the case excessively meagre and though wheat may readily cross with Ægylops that is no argument against—15 Wheat has never been seen indigenous, and it rarely if ever escapes from cultivation in Europe, I mean so as to persist in a second generation from seed accidentally dropped—and not for certain in the Levant and South Russia where the cultivated wheat is less removed from the wild state in character as well as in treatment.

Has it occurred to you that a ready reply to the argument that plants do not vary in botanic gardens (besides a flat denial) is that generally speaking selection acts the other way   Curators are always desirous of having their seeds true and generally save from the individuals truest to their type.16

You mention the Cynara cardunculus having acquired a gregarious character in S. America which it has not in Europe—I believe it would be gregarious in Europe if it were allowed.17 In the West Mediterranean regions where it appears to be indigenous the apparently waste lands where it thrives though unenclosed are all under a certain degree of cultivation—all are fed off in the autumn winter and spring by sheep and goats whose shepherds take good care to prevent the overgrowth of large thistles. You mention the artichoke as one of the plants which has not varied much under cultivation18 Here it is rarely sown—in Eastern Europe it is little grown—in the Mediterranean region where it is very largely cultivated and especially in some parts of France where it has long been grown both for the involucre & receptacles and for the leaf stalks for blanching it has varied considerably and there are often intermediates between the Cardoon and Artichoke which I believe not to be crosses but improved Cardoons. Involucral bracts as prickly as those of the Cardoon but the heads and bottoms as large as a poor Artichoke   Old French gardening books enumerate a considerable number of varieties of which six most distinct and valuable and recommend sowing as a sure means of producing new and good varieties.

After bothering you with all the above which of course requires no answer it is too hard to ask you questions but if you have a moment to reply to the following you would much oblige me

What is your opinion of Hildebrands19 observations whom French critics accuse of being carried too far as to the constancy of cross fertilisation and what are his chief publications on the subject

Who are the principal observers who have been following up your observations besides John Scott and Fritz Müller.

Your paper on the Primrose Cowslip and Oxlip20 interested me much but there is something still not quite clear to me—the variations of the Cowslip in countries where there is little or no Primrose—the absence of Oxlip in many countries or districts where both Cowslip and Primrose are abundant and the number of individual Oxlips in the very few places where I have seen much of it are not the conditions in which I have so much observed hybrid Verbascums Cistuses etc in the S. of France or hybrid Saxifragas in the Pyrenees. Hybrid thistles of which so much has been said by German and French local botanists are really exceedingly few in individuals

Your paper was followed the next meeting by one from Buckman on the rapid change he had effected in the Parsnip in which Vilmorin never could succeed—21 and some other matters of little importance about Radishes etc. but I must say I cannot have anything like the confidence in his experiments that we all have in yours. When he showed me over his experimental ground at Cirencester some eight or ten years ago one could not be struck how few were the precautions against error—substitution of one plant for another—unintended hybridisation etc, and when he afterwards professed to have raised Avena fatua from Avena sativa and Trifolium repens from Trifolium hybridum it appeared to me to be a case similar to the transmutation of oats into Rye etc that poor Lindley took up at one time—one plant sown in a pot and another coming up without any further proof that the latter actually came from the seed sown22

Have you ever met with Olivier de Serres Theatre d’Agriculture23 a work as far as I can recollect of the seventeenth century in which is much valuable information as to the agriculture of that day in the south of France which had remained pretty well stationary up to the time when we lived there half a century ago— We had the book but it was afterwards stolen from us and I have not been able to hear of a copy here   There has been so long so much of tree-cultivation and tree-sowing in Mediterranean France with so little of permanent result that it might be interesting to trace the history of the practices of the country   In those hot dry climates there seems to be so much more of propagation by seed compared to propagation by bud (I speak of wild not cultivated plants) than in our cold damp countries that there ought to be a much greater readiness for variation there than here.

You are aware I believe that most botanists distinguish as species Alliums that bear bulbs instead of or mixed with the flowers in the umbel from those which do not— from long observation I am convinced that these bulb bearing species are mere varieties—or rather states of the non-bulb-bearing corresponding ones and in some instances I have known the bulbbearing individuals transplanted into a good many garden cease to produce bulbs.

Ever yours sincerely | George Bentham

I am glad to see your remarks on Acclimatisation   I am one of those who have always treated Acclimatisation as it is understood by Acclimatisation Societies as a vain chimera but then that is the attempt at acclimating individuals—or varieties without selection which when it has been supposed to be successful has been merely introducing a suitable race new to the country from a different country   It is to be hoped that the attention of these societies may be called to the importance of your principles in showing them how to acclimatise races by selection24

Have you ever seen Sagot’s papers on the cultivated plants of Cayenne which have some interesting observations on the effects of the climate on European plants preventing their flowering and causing a great development of vegetative organs.25

* 5ft 5in English

CD annotations

1.1 At … fire 1.10] crossed pencil
2.1 First … type. 5.4] crossed ink
3.1 Phaseolus vulgaris] after opening square bracket, blue crayon; underl blue crayon
3.11 Savi … species— 3.12] scored blue crayon
3.17 “there … cultivated.” 3.20] scored blue crayon
4.1 I cannot] ‘Wheat’ added before, blue crayon
5.1 Has … type. 5.4] enclosed in square brackets, pencil
6.7 artichoke] after opening square bracket, blue crayon
6.11 it has varied … Cardoons. 6.13] scored blue crayon
6.14 Old … varieties. 6.16] scored blue crayon
7.1 After … subject 8.3] crossed pencil
10.1 Your … organs. 16.3] crossed pencil
Top of letter: ‘Asses used for [2 words illeg] Edition’26 pencil; ‘Artichoke does vary’ red crayon; ‘Artichoke’27 blue crayon, circled red crayon; illeg, pencil; illeg, blue crayon del pencil; illeg, blue crayon circled red crayon


The date is established by the relationship between this letter and the letter to George Bentham, 22 April 1868.
Bentham was co-author of the multi-volume work Genera plantarum (Bentham and Hooker 1862–83). Bentham refers to Variation.
CD discussed reversion and pangenesis, his hypothesis of heredity, in Variation 2: 28–61, and 357–404. Bentham alludes to CD’s statement in the introduction that Variation would be the first of three related works covering domestic variation, variation in the wild, and the principle of natural selection (Variation 1: 8–10).
Poitou, Perigord, and Limousin are regions of western and south-western France.
Saumur is a town in the Loire valley in western France.
Bentham refers to Pierre-Etienne Herbin de Halle and Statistique générale et particulière de la France et de ses colonies (Herbin de Halle ed. 1803–4, 1: 262–3). Aside from minor errors, Bentham’s transcription of the passage is accurate. Translation of the excerpt: Their usual height is from 1 metre 40 to 50 centimetres (4 feet 3 to 6 inches), and there are some of 1 metre 67 centimetres (5 feet) … They are very thick-set; their legs are almost as strong as those of cart-horses, their hair is between 16 and 17 centimetres (6 inches) in length, the dimension of their hoofs is double that. They are said to be very vicious and wild, and are tied up with chains of iron; they can service nearly a hundred mares in season, live for nearly twenty years and die of old age. The most highly valued are those with very black hair.
The reference is to Charles-Nicolas-Sigisbert Sonnini de Manoncourt, and the quotation is from an entry on the ass by Sonnini in the Nouveau Dictionnaire d’Histoire Naturelle (1: 370–83) published by Francois-Pierre Deterville. Bentham’s transcription of the passage on page 381 contains a few minor errors. Translation of the excerpt: They are only used as stallions and as they are never shod their hoof horn elongates in a disagreeable way … they are are priced highly according to their height, and above all the width and thickness of their hocks; some have fetched five hundred ecus or even as much as three or four thousand livres apiece; the black ones are most prized.
Phaseolus vulgaris is the kidney bean.
Soissons is a town in northern France on the Aisne river. The Soissons variety of Phaseolus vulgaris, still a popular variety, is very large and white.
In his paper on the genera Phaseolus and Dolichos (Savi 1822), Gaetano Savi identified five species of Phaseolus. ‘Haricot-riz’: rice bean (called Phaseolus chrysanthos by Savi, now Vigna umbellata). Bentham also refers to Augustin Pyramus de Candolle and A. P. de Candolle 1825 (see p. 381 for Candolle’s reference to Savi’s work on Phaseolus and Dolichos). CD added Bentham’s information on Savi and varieties of Phaseolus in Variation 2d ed. 1: 350 n. 93.
The source of the quotation has not been identified.
Nickol Bay is in the northern part of the present state of Western Australia between Cape Lambert and Cape Preston (W. H. Wells 1848).
The scarlet runner bean is now Phaseolus coccineus. In Cross and self fertilisation, p. 150, CD mentioned that Bentham told him the plant (which he referred to as P. multiflorus) was of Mexican origin.
Vigna is a bean genus, closely related to Phaseolus.
Bentham refers to CD’s discussion of the origin of wheat (see Variation 1: 312–13). CD cited Alphonse de Candolle (A. de Candolle 1855, 2: 928–36) for the view that Triticum vulgare had been found wild in parts of Asia. CD cited Bentham for the view that none of the cultivated grains mentioned existed in the wild. Triticum vulgare (now T. aestivum, common wheat), T. spelta (spelt), and T. monococcum (einkorn) are all cultivated grains. Aegilops (goatgrass) is a grass genus with several extant species.
See Variation 2: 237.
Cynara cardunculus is the cardoon. See Variation 2: 34.
Cynara scolymus (the globe artichoke), was believed to be descended from C. cardunculus (cardoon). In Variation 2: 34, CD mentioned only C. cardunculus, and said he did not know whether it differed in any important point from cultivated varieties (that is, artichokes).
Bentham refers to ‘Specific difference in Primula, which was read at the Linnean Society on 19 March 1868.
Bentham refers to James Buckman, whose paper ‘The effects of selection in the cultivation of plants’ was read at the 2 April 1868 meeting of the Linnean Society (Proceedings of the Linnean Society of London (1867–8): l). The paper was not published. In Variation 1: 326, CD referred to the work of Buckman on parsnips, which he compared to that of Louis de Vilmorin on carrots.
The Royal Agricultural College, where Buckman was professor of botany from 1848 to 1863, was at Cirencester. Avena fatua: wild oats; Avena sativa: oats; Trifolium repens: white clover; Trifolium hybridum: alsike clover. For John Lindley’s belief in the transmutation of oats into rye, see Correspondence vol. 3, letters from J. D. Hooker, [late February 1845] and n. 5, and [23] March 1845.
Bentham refers to Olivier de Serres and Le théâtre d’agriculture et mesnage des champs (Serres 1600). Serres covered a wide range of topics from crop rotation to farm hygiene; his book went through numerous editions and had a long-lasting influence on agricultural practice in France well into the nineteenth century (Boulaine and Moreau 2002, pp. 83 et seq.).
See Variation 2: 305–15. For more on the history and aims of acclimatisation societies, especially in the nineteenth century, see Lever 1992.
Bentham refers to Paul Antoine Sagot and to Sagot’s work on domestication of plants. See, for example, Sagot 1865a.
In Variation 2d ed., 1: 65, CD added information on the size of asses in the south of France, but did not cite Bentham (see n. 6, above).
CD cited Bentham for information on the varieties of artichokes in Variation 2d ed., 2: 222.


Candolle, Alphonse de. 1855. Géographie botanique raisonnée ou exposition des faits principaux et des lois concernant la distribution géographique des plantes de l’époque actuelle. 2 vols. Paris: Victor Mason. Geneva: J. Kessmann.

Candolle, Augustin Pyramus de. 1825. Mémoires sur la famille des légumineuses. Paris: A. Belin.

Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.

Cross and self fertilisation: The effects of cross and self fertilisation in the vegetable kingdom. By Charles Darwin. London: John Murray. 1876.

Lever, Christopher. 1992. They dined on eland: the story of the acclimatisation societies. London: Quiller Press.

Savi, Gaetano. 1822. Osservazioni sopra i generi Phaseolus et Dolichos. Nuovo Giornale de’Letterati 3: 302–19.

Serres, Olivier de. 1600. Le théâtre d’agriculture et mesnage des champs. Paris: I. Metayer.

‘Specific difference in Primula’: On the specific difference between Primula veris, Brit. Fl. (var. officinalis of Linn.), P. vulgaris, Brit. Fl. (var. acaulis, Linn.), and P. elatior, Jacq.; and on the hybrid nature of the common oxlip. With supplementary remarks on naturally produced hybrids in the genus Verbascum. By Charles Darwin. [Read 19 March 1868.] Journal of the Linnean Society (Botany) 10 (1869): 437–54.

Variation 2d ed.: The variation of animals and plants under domestication. By Charles Darwin. 2d edition. 2 vols. London: John Murray. 1875.

Variation: The variation of animals and plants under domestication. By Charles Darwin. 2 vols. London: John Murray. 1868.

Wells, William Henry. 1848. Geographical dictionary; or gazetteer of the Australian colonies. Sydney: W. & F. Ford.


Has studied Variation with interest.

Cannot quite follow CD on reversion and Pangenesis,

but is amazed at CD’s observations and method.

Comments on varieties of asses, kidney beans, and artichokes.

Letter details

Letter no.
George Bentham
Charles Robert Darwin
Sent from
London, Wilton Place, 25
Source of text
DAR 160: 160
Physical description
ALS 11pp damaged †

Please cite as

Darwin Correspondence Project, “Letter no. 6134,” accessed on 13 September 2023,

Also published in The Correspondence of Charles Darwin, vol. 16