To Gaston de Saporta   24 December 1877

Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.

Dec 24. 1877

Mr dear Sir,

I thank you sincerely for your long & most interesting letter, which I should have answered sooner had it not been delayed in London.1 I had not heard before that I was to be proposed as a Corr: Member of the Institute.2 Living so retired a life as I do, such honours affect me very little; & I can say with entire truth that your kind expression of sympathy has given, & will give me much more pleasure than the election itself, should I be elected.

Your idea that dicotyledonous plants were not developed in force until sucking insects had been evolved seems to me a splendid one.3 I am surprised that the idea never occurred to me, but this is always the case when one first hears a new & simple explanation of some mysterious phenomenon. It’s the old story of Columbus & the egg.4 I formerly showed that we might fairly assume that the beauty of flowers, their sweet odour & copious nectar, may be attributed to the existence of flower-haunting insects but your idea, which I hope you will publish, goes much further & is much more important.5 With respect to the great development of mammifers in the later Geological periods following from the development of dicotyledons, I think it ought to be proved that such animals as deer, cows, horses &c could not flourish if fed exclusively on the gramineæ & other anemophilous monocotyledons; & I do not suppose that any evidence on this head exists.6

Your suggestion of studying the manner of fertilisation of the surviving members of the most ancient forms of the dicotyledons is a very good one, & I hope that you will keep it in mind yourself, for I have turned my attention to other subjects. Delpino I think says that Magnolia is fertilised by insects which gnaw the petals, & I should not be surprised if the same fact holds good with Nymphaea.7 When ever I have looked at the flowers of these latter plants, I have felt inclined to admit the view that petals are modified stamens & not modified leaves; though Pointsettia seems to show that true leaves might be converted into coloured petals.8 I grieve to say that I have never been properly grounded in Botany & have studied only special points: therefore I cannot pretend to express any opinion on your remarks on the origin of the flowers of the Coniferæ, Gnetaceæ &c; but I have been delighted with what you say on the conversion of a monœcous species into a hermaphrodite one by the condensations of the verticels on a branch bearing female flowers near the summit & male flowers below. Mr Thiselton Dyer, in a review of my book in Nature, objected on morphological grounds to a somewhat similar notion; but did not explain what these grounds were.9

With respect to persistent types your cases are curiously analogous to those which occur in many groups of the animal kingdom & have been commented on by Huxley.10

I expect Hooker to come here before long, & I will then show him your drawing & if he makes any important remarks I will communicate with you.11 He is very busy at present in clearing off arrears after his American expedition, so that I do not like to trouble him even with the briefest note.12

I am at present working with my son at some physiological subjects & we are arriving at very curious results, but they are not as yet sufficiently certain to be worth communicating to you.13 I do not know whether you feel any interest about insectivorous plants: my son Francis fed with meat last summer a large number of plants of Drosera rotundifolia & left others unfed by excluding insects; & the difference between the two sets of plants in growth, & especially in the number & weight of the seeds was truly wonderful. He has sent a paper on this subject to the Linnean Soc a copy of which he will hereafter send to you.14

With my best thanks & the greatest respect, I remain, my dear Sir | Yours faithfully

L

2
CD had been nominated for membership of the botanical section of the Académie des sciences. See letter from Gaston de Saporta, 16 December 1877 and n. 2.
3
Dicotyledons are flowering seed-plants, or angiosperms, characterised by the presence of two embryonic seed-leaves or cotyledons; CD had remarked that the sudden appearance of so many dicotyledons was ‘most perplexing’, and conjectured that the plants had first developed in an isolated region and then spread quickly when geographical conditions became favourable (Correspondence vol. 23, letter to Oswald Heer, 8 March [1875]).
4
CD refers to the apocryphal story about Christopher Columbus’s challenge to a group of men to make an egg stand on end; when none was successful, Columbus tapped the end, cracking the egg slightly to flatten the tip, after which it stood easily. The story illustrates the fact that a brilliant idea often seems obvious or simple in retrospect.
5
CD discussed beauty in flowers and its relation to insect visitors in Origin 4th ed., pp. 239–40.
6
In his letter of 16 December 1877, Saporta argued that the evolution of plant-eating mammals was linked to development in the plant kingdom.
7
Federico Delpino discussed the fertilisation of Magnolia species aided by beetles of the genus Cetonia in Delpino 1868–75, 2: 234–5. He discussed the beetle’s gnawing of another flower, Paeonia moutan (a synonym of P. suffruticosa), which he included as a flower type like Magnolia in ibid., p. 236. Nymphaea is the genus of waterlilies.
8
Poinsettia is the common name of Euphorbia pulcherrima; its bright red bracts, or modified leaves, are often mistaken for petals.
9
In his letter of 16 December 1877, Saporta had argued that the verticils or whorls of the corolla were converging spiral turns. He also suggested that the contraction of sexual branches bearing what he termed androphylls and carpophylls (male and female parts of modified leaves) resulted in the formation of hermaphrodite flowers. In his review of Cross and self fertilisation (Thiselton-Dyer 1877, p. 331), William Turner Thiselton-Dyer had discussed CD’s view that a monoecious condition was the first step to hermaphroditism and offered an opposing explanation that the earliest angiosperms were hermaphrodites.
10
See letter from Gaston de Saporta, 16 December 1877 and n. 11. Thomas Henry Huxley had discussed the persistence of animal types in his anniversary address to the Geological Society of London (T. H. Huxley 1862; for a discussion of Huxley’s views on this point, see A. Desmond 1982, pp. 85–112).
11
Saporta had sent CD a tracing of a fossil leaf and asked whether Joseph Dalton Hooker could examine it and suggest a comparison (see letter from Gaston de Saporta, 16 December 1877 and n. 26).
12
Hooker had spent July and August 1877 travelling in the United States (see letter from J. D. Hooker, 19 October 1877 and n. 3).
13
CD and Francis Darwin were studying the physiology of plant movement; their findings were published in Movement in plants in 1880.
14
Drosera rotundifolia is the common or round-leaved sundew. Francis Darwin’s paper (F. Darwin 1878a) was read at the Linnean Society on 17 January 1878 and published in the Journal of the Linnean Society (Botany).

Please cite as “DCP-LETT-11287,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-11287