To J. D. Hooker 28 November [1871]
Summary
CD is considering repeating experiments on melastomads in which different pollen sizes produced differing seedling sizes.
Responds to JDH’s query on differences in pollen within the same species.
| Author: | Charles Robert Darwin |
| Addressee: | Joseph Dalton Hooker |
| Date: | 28 Nov [1871] |
| Classmark: | DAR 95: 445–8 |
| Letter no: | DCP-LETT-8087 |
Matches: 16 hits
- … on melastomads in which different pollen sizes produced differing seedling sizes. …
- … Responds to JDH’s query on differences in pollen within the same species. …
- … fertilised separately by the two kinds of pollen, & the seedlings differed remarkably in …
- … of stamens carrying differently coloured pollen (red and pale yellow). CD’s diagrams and …
- … for my notes. — You ask about difference in pollen in the same species. All dimorphic & …
- … Oxalis are the most wonderful cases. The pollen of the closed imperfect cleistogenic …
- … point I c d ascertain from my notes. — The pollen or female organs must differ in almost …
- … individual in some manner; otherwise the pollen of vars. & even distinct individuals of …
- … same vars would not be so preptent over the individual plants own pollen. Here follows …
- … of individual difference in function of pollen or ovules or both. Some few individuals of …
- … of R . lutea , cannot be fertilised, or only very rarely, by pollen of same plant, …
- … but can by pollen of any other individual. I chanced to have 2 plants of R. …
- … self-sterile & all perfectly fertile with pollen of any other individual mignonette. So I …
- … For a discussion of the relative size of pollen-grains in dimorphic and trimorphic plants, …
- … Forms of flowers , pp. 248–52. The pollen-grains of cleistogamic flowers have especially …
- … p. 310). CD measured the size of pollen-grains in cleistogamic flowers of Viola canina …
To A. W. Bennett [before 16 November 1871]
Summary
Discussed observations made in 1863 of Impatiens pollen and humble-bees.
| Author: | Charles Robert Darwin |
| Addressee: | Alfred William Bennett |
| Date: | [before 16 Nov 1871] |
| Classmark: | Journal of the Linnean Society (Botany) 13 (1873): 152 |
| Letter no: | DCP-LETT-8303F |
Matches: 11 hits
- … Discussed observations made in 1863 of Impatiens pollen and humble-bees. …
- … plant probably requiring repeated doses of pollen, as is certainly sometimes the case. …
- … anthers, and the very small quantity of pollen. The grains are of the same diameter as in …
- … be more unequal in size. I distinctly saw pollen-grains protruding from the grains whilst …
- … on an average 3.45 seeds. I carefully brushed away the pollen from some of the perfect …
- … flowers, and fertilized them with pollen from a distinct plant, but got only three pods, …
- … had argued, ‘the state of corolla, of stigma & pollen-grains [in cleistogamic flowers] is …
- … 1862 ). CD’s observations on the anthers and pollen of both perfect (CD uses ‘perfect’ to …
- … I do not mention in my notes that the pollen-grains are tied together by threads, as …
- … I do in the case of the pollen of the perfect flowers. I speak of the nectary in the …
- … flowers containing nectar, and from the pollen-grains being tied together by threads, I …
To Gardeners’ Chronicle [31 August 1871]
Summary
In response to a query [from "F. W. B."], CD describes his experience with seeding Leschenaultia, which demonstrates that insect agency is required.
| Author: | Charles Robert Darwin |
| Addressee: | Gardeners’ Chronicle |
| Date: | [31 Aug 1871] |
| Classmark: | Gardeners’ Chronicle, 9 September 1871, p. 1166 |
| Letter no: | DCP-LETT-7927 |
Matches: 13 hits
- … anthers, and is preserved intact from any pollen that may be inserted * * by insects or …
- … the flower expands, the anthers open and the pollen is shed. This occurs in a considerable …
- … self-fertilisation. In Leschenaultia the pollen, when shed, is neatly collected in a cup- …
- … find, on further examination, that the pollen must, in order that the flower should be …
- … and when on two occasions I placed some pollen-grains on the surface, I found, after an …
- … that it was deeply penetrated by numerous pollen-tubes. I was so much surprised at this …
- … opens it; and some of the hairs enter and become smeared with pollen. If the same …
- … be now successively inserted into several flowers, pollen-grains will be found left on the …
- … not subserve its proper function of producing pollen, but has been converted into a short …
- … such a position that it cannot receive pollen from the fertile anthers of the same flower; …
- … germinate. The flowers were necessarily fertilised with pollen from the same plant, but it …
- … would have been incomparably better if pollen from a distinct seedling plant could have …
- … in this genus and in some allied genera, the pollen, whilst the flowers are still in bud, …
From H. G. Cavendish Browne 26 July 1871
Summary
Reports that a humble-bee fertilised a tropical orchid in his hothouse.
| Author: | H. G. Cavendish Browne |
| Addressee: | Charles Robert Darwin |
| Date: | 26 July 1871 |
| Classmark: | DAR 160: 328 |
| Letter no: | DCP-LETT-7882 |
Matches: 6 hits
- … of the anther, and that the presence of pollen masses on his back would not have disturbed …
- … the spring and withdrawal of the bloom’s own pollen-masses being reserved for his backward …
- … one flower shall be fertilised by the pollen of another. I remain, Sir, | very faithfully …
- … expanse of the labellum with the two large pollen masses firmly adhering to the ‘small’ of …
- … went in as far as before, now bearing the pollen masses on his back. He returned in about …
- … had expended there previously,) leaving both pollen-masses on the stigma; the discs alone …
To Fritz Müller 2 August [1871]
Summary
Opinions on Descent.
Sexual selection and mimicry in Lepidoptera; sexual selection as an aid to protective imitation.
| Author: | Charles Robert Darwin |
| Addressee: | Johann Friedrich Theodor (Fritz) Müller |
| Date: | 2 Aug [1871] |
| Classmark: | The British Library (Loan MS 10 no 34) |
| Letter no: | DCP-LETT-7892 |
To J. D. Hooker 5 July [1871]
Summary
Lady Lyell’s anxiety over Lyell’s health.
Preparing new edition of Origin.
Asks whether anything was observed [in Morocco] on expressions.
Did JDH notice whether pollen-masses in Ophrys apifera in N. Africa fall on the stigma, as in England?
| Author: | Charles Robert Darwin |
| Addressee: | Joseph Dalton Hooker |
| Date: | 5 July [1871] |
| Classmark: | DAR 94: 197–8 |
| Letter no: | DCP-LETT-7850 |
To Friedrich Hildebrand 10 August [1871]
Summary
Mentions experiments on Lythrum.
Thanks for list of seeds.
| Author: | Charles Robert Darwin |
| Addressee: | Friedrich Hermann Gustav (Friedrich) Hildebrand |
| Date: | 10 Aug [1871] |
| Classmark: | Klaus Groove (private collection); sold by Venator and Hanstein, Cologne (dealers), 16 March 2018 |
| Letter no: | DCP-LETT-7902 |
From Federico Delpino 7 January 1871
Summary
Sends his new work, Ulteriori osservazioni sulla dicogomia pt 2, fasc. 1.
Has found no nectar in Orchis morio or O. maculata in Italy and has seen no insects visiting the plants.
Gives his observations on cross- and self-fertilisation in cereals.
| Author: | Federico Delpino |
| Addressee: | Charles Robert Darwin |
| Date: | 7 Jan 1871 |
| Classmark: | DAR 111: A77–8 |
| Letter no: | DCP-LETT-7430 |
Matches: 4 hits
- … insects in the act in Liguria; there the pollen-masses that are carried away are most …
- … can fertilise itself, since part of the pollen is turned towards the flower and the other …
- … if for a short time only, and half the pollen is turned outwards to the air, at the mercy …
- … another, so as to exclude heterocline pollen, still develop all the seeds. For triticum , …
From Patrick Matthew 12 March 1871
Summary
Encloses an article he wrote for the Scotsman [9 Mar 1871, p. 5].
Wishes he had time to write a critique of Descent. There is evidence of design and benevolence in nature. Beauty cannot be accounted for by natural selection.
| Author: | Patrick Matthew |
| Addressee: | Charles Robert Darwin |
| Date: | 12 Mar 1871 |
| Classmark: | Natural History Museum, Library and Archives (General Library) |
| Letter no: | DCP-LETT-7576 |
To John Scott 1 November 1871
Summary
JS should not consider repaying CD; the money was a gift, not a loan.
JS’s information on expression is the best he has received.
| Author: | Charles Robert Darwin |
| Addressee: | John Scott |
| Date: | 1 Nov 1871 |
| Classmark: | DAR 185: 111 |
| Letter no: | DCP-LETT-8045 |
To J. D. Hooker 21 March [1871]
Summary
Asks name of an Abutilon from Fritz Müller.
Questions about Drosophyllum for experiments;
the meaning of "Sirdar".
Wonderful success of Descent. Astonished by liberality of public. No abuse yet.
Marvels at JDH’s plans for a trip to Morocco. Asks him to look for alpine insects.
| Author: | Charles Robert Darwin |
| Addressee: | Joseph Dalton Hooker |
| Date: | 21 Mar [1871] |
| Classmark: | DAR 94: 190–192 |
| Letter no: | DCP-LETT-7607 |
To J. D. Hooker 23 July [1871]
Summary
Honoured by Abutilon name; describes observations on its fertilisation.
Henrietta’s marriage a great loss to him.
Latest Quarterly Review has article, "evidently by Mivart", that cuts CD into mincemeat.
Asks for name of species of mouse J. S. Henslow used to keep [see 598].
| Author: | Charles Robert Darwin |
| Addressee: | Joseph Dalton Hooker |
| Date: | 23 July [1871] |
| Classmark: | DAR 94: 199–200 |
| Letter no: | DCP-LETT-7878 |
To Nature [before 27 April 1871]
Summary
Replies to Francis Galton’s paper on tranfusing blood between rabbits to test Pangenesis [Proc. R. Soc. Lond. 19 (1871): 393–40]. FG’s conclusion that his experiments prove Pangenesis to be false is "a little hasty", since CD had never maintained that gemmules in the blood formed any part of his hypothesis.
| Author: | Charles Robert Darwin |
| Addressee: | Nature |
| Date: | [before 27 Apr 1871] |
| Classmark: | Nature, 27 April 1871, pp. 502–3 |
| Letter no: | DCP-LETT-7720 |
From Henry Reeks 25 May 1871
Summary
Comments on and corrections for chapter 13, "Mammals", of Descent.
| Author: | Henry Stephen (Henry) Reeks |
| Addressee: | Charles Robert Darwin |
| Date: | 25 May 1871 |
| Classmark: | DAR 88: 100–4 |
| Letter no: | DCP-LETT-7767 |
Matches: 1 hit
- … come forth some few days previously— The pollen on the anthers of flowering plants is …
| letter | (14) |
| Darwin, C. R. | (10) |
| Browne, H. G. C. | (1) |
| Delpino, Federico | (1) |
| Matthew, Patrick | (1) |
| Reeks, Henry | (1) |
| Darwin, C. R. | (4) |
| Hooker, J. D. | (4) |
| Bennett, A. W. | (1) |
| Gardeners’ Chronicle | (1) |
| Hildebrand, Friedrich | (1) |
| Darwin, C. R. | (14) |
| Hooker, J. D. | (4) |
| Bennett, A. W. | (1) |
| Browne, H. G. C. | (1) |
| Delpino, Federico | (1) |
Forms of flowers
Summary
Darwin’s book The different forms of flowers on plants of the same species, published in 1877, investigated the structural differences in the sexual organs of flowers of the same species. It drew on and expanded five articles Darwin had published on the…
Matches: 15 hits
- … male flowers on separate plants) and also noted that their pollen differed in size and shape. He …
- … of Primrose & Cowslip with short pistils & large-grained pollen are rather more fertile …
- … of my experiments lead me to suspect that the large-grained pollen suits the long pistils & the …
- … I think I have made out their good or meaning clearly. The pollen of A is fitted for stigma of B …
- … both terms referred to the fertilisation of one form with pollen from the same form. At this late …
- … two forms and that one of these was absolutely sterile with pollen from the same form, while the …
- … explained to Gray, ‘ I have lately been putting the pollen of the two forms on the division of the …
- … me as truly wonderful, that the stigma distinguishes the pollen; & is penetrated by the tubes of …
- … he told Hooker, ‘ In function, but not in appearance, the pollen of these two forms, as tested by …
- … is so frequent in truly hermaphrodite groups; namely the pollen & stigma of each flower being …
- … of the plant, with dotted lines indicating which pollen must be applied to each stigma to produce …
- … He told Gray in October 1865 that with respect to its own pollen, the long-styled form was …
- … plants raised from Dimorphic species fertilized by their own pollen, are themselves generally …
- … in a few specimens. It is necessary to compare size of pollen grains & state of stigma ’. …
- … ‘I will rank no plant as dimorphic without comparing pollen-grains & stigmas’. When Hermann …
Charles Harrison Blackley
Summary
You may not have heard of Charles Harrison Blackley (1820–1900), but if you are one of the 15 million people in the UK who suffer from hay fever, you are indebted to him. For it was he who identified pollen as the cause of the allergy. Darwin was…
Matches: 11 hits
- … fever, you are indebted to him. For it was he who identified pollen as the cause of the allergy, and …
- … 5 July 1873 Darwin wrote again, saying: ‘The power of pollen in exciting the skin & mucous …
- … changes in his own symptoms, that he was able to single out pollen as the only credible cause. …
- … He also experimented with fresh, dry and extracts of pollen, administered to his nose, mouth, eyes …
- … writes: Perhaps where grass is cut & dried; some pollen of the entomophilous division …
- … was fascinated by Blackley’s experiments testing whether pollen could be carried large distances in …
- … p. 5). Darwin gave a further example of how coniferous pollen could be carried for hundreds of miles …
- … with carbolic acid to deter insects. He concluded that in pollen seasons much higher levels were …
- … from hay fever in large cities far away from sources of pollen. In his later work, possibly …
- … Blackley tried to find out the smallest amount of pollen that would initiate and maintain the …
- … recommending spending summers in suitable locations to avoid pollen. But his lasting contribution …
Cross and self fertilisation
Summary
The effects of cross and self fertilisation in the vegetable kingdom, published on 10 November 1876, was the result of a decade-long project to provide evidence for Darwin’s belief that ‘‘Nature thus tells us, in the most emphatic manner, that she abhors…
Matches: 20 hits
- … flowers and the physiological effects of different forms of pollen. Although many plants that Darwin …
- … many of these were nevertheless fertile with their own pollen. He set out to compare several …
- … of the young plants when raised from a pistil fertilized by pollen from the same flower, & from …
- … that Darwin would confirm that this poppy shed its pollen immediately after the flower opened, …
- … since even those flowers to which he applied foreign pollen had probably already been self …
- … on which he commented, ‘This complete infertility with own pollen could hardly have remained …
- … you w d care, is that a great excess of, or very little pollen produced not the least difference …
- … On the other hand seeds from this plant, fertilised by pollen from the same flower, weigh less, …
- … beginning to suspect that the insects which could transfer pollen in sweet peas simply did not exist …
- … mignonette ( Reseda odorata ) was absolutely sterile with pollen from same plant in spite of the …
- … there sh d be some difference in ovules & contents of pollen-grains (for the tubes penetrate …
- … the same plant!’ ( To J. D. Hooker, 21 May [1868] ) Pollen tubes, or rapidly elongating vegetative …
- … ovary of a flower; they are triggered to elongate when the pollen touches the stigmatic surface. …
- … at the lessened fertility when he pollinated plants using pollen from other plants of the same …
- … the early part of the flowering season quite sterile with pollen from the same plant, though fertile …
- … as adults forever fixed in close proximity to others, so pollen from widely separated flowers could …
- … stylar forms of flowers, Darwin had referred to unions where pollen from one form had been applied …
- … that some forms were absolutely sterile with their own pollen while others had varying degrees of …
- … Ernst Haeckel, ‘It is really wonderful what an effect pollen from a distinct seedling plant which …
- … forms of flowers that showed sterility could exist when pollen from one form was applied to the same …
A fly on the flower: From Hermann Müller, 23 October 1867
Summary
In March 1867, Hermann Müller, a young teacher of natural sciences at a provincial Realschule (a type of secondary school that emphasised the natural sciences) in Lippstadt in the Prussian province of Westphalia, sent Darwin two papers on the mosses of…
Matches: 4 hits
- … order to observe their adaptations for collecting nectar and pollen. A letter he wrote in October …
- … of the hoverfly mouthparts that are specially adapted for pollen eating. Müller’s discovery seemed …
- … as pseudotracheae), which were the perfect size for holding pollen grains. He further noted, having …
- … in different species, depending on the size of the pollen eaten by each type of fly. It is amazing …
Floral Dimorphism
Summary
Sources|Discussion Questions|Experiment Floral studies In 1877 Darwin published a book that included a series of smaller studies on botanical subjects. Titled The different forms of flowers on plants of the same species, it consisted primarily of…
Essay: Evolutionary teleology
Summary
—by Asa Gray EVOLUTIONARY TELEOLOGY When Cuvier spoke of the ‘combination of organs in such order that they may be in consistence with the part which the animal has to play in Nature,’ his opponent, Geoffroy St.-Hilaire, rejoined, ‘I know nothing of…
Matches: 14 hits
- … meaning. One good illustration of it is furnished by the pollen of flowers. The seeming waste of …
- … ’ which every one has heard of. Myriads upon myriads of pollen-grains (each an elaborate organic …
- … a violet, in which there are not many times more grains of pollen produced than there are of seeds …
- … other flowers also, provided with a large surplus of pollen, and endowed (as the others are not) …
- … to certain insects, which are thereby induced to convey this pollen from blossom to blossom, that it …
- … of which are committed to insects, the likelihood that much pollen may be left behind or lost in the …
- … in orchis-flowers is accounted for by the fact that the pollen is packed in coherent masses, all …
- … against it when it sucks nectar from the flower, and so the pollen will be bodily conveyed from …
- … case, that of pine-trees, the vast superabundance of pollen would be sheer waste if the intention …
- … ’ as the means, no one is entitled to declare that pine-pollen is in wasteful excess. The cheapness …
- … involved in similar difficulty. The superabundance of the pollen of pine-trees above referred to, …
- … In the analogous instance of willows a diminished amount of pollen is correlated with direct …
- … difference in the conveyance would reduce the quantity of pollen produced. It is, we know, in the …
- … work and material; but why should it begin to produce less pollen? But this is as nothing compared …
Orchids
Summary
Sources|Discussion Questions|Experiment A project to follow On the Origin of Species Darwin began to observe English orchids and collect specimens from abroad in the years immediately following the publication of On the Origin of Species. Examining…
From morphology to movement: observation and experiment
Summary
Darwin was a thoughtful observer of the natural world from an early age. Whether on a grand scale, as exemplified by his observations on geology, or a microscopic one, as shown by his early work on the eggs and larvae of tiny bryozoans, Darwin was…
Hermann Müller
Summary
Hermann (Heinrich Ludwig Hermann) Müller, was born in Mühlberg near Erfurt in 1829. He was the younger brother of Fritz Müller (1822–97). Following the completion of his secondary education at Erfurt in 1848, he studied natural sciences at Halle and Berlin…
Orchids
Summary
Why Orchids? Darwin wrote in his Autobiography, ‘During the summer of 1839, and, I believe, during the previous summer, I was led to attend to the cross-fertilisation of flowers by the aid of insects, from having come to the conclusion in my…
Matches: 5 hits
- … puzzles me.— The Fly-Ophrys seems hardly ever to get its pollen masses moved at all, & the …
- … agency—another part, namely the natural falling out of the pollen-masses, being adapted for self …
- … in which I ask for information on what kinds of moths the pollen-masses of Orchids have been found …
- … Hooker, ‘ I shall never rest till I see a Catasetum eject pollen-masses, & a Mormodes twist its …
- … not only because of its remarkable ability to eject its pollen masses like a catapult, but also …
The evolution of honeycomb
Summary
Honeycombs are natural engineering marvels, using the least possible amount of wax to provide the greatest amount of storage space, with the greatest possible structural stability. Darwin recognised that explaining the evolution of the honey-bee’s comb…
Fool's experiments
Summary
‘I love fools' experiments. I am always making them’, was one of the most interesting things the zoologist E. Ray Lankester ever heard Darwin say. ‘A great deal might be written as comment on that statement’, Lankester later recorded, but he limited…
Matches: 1 hits
- … to Lankester involved placing under a bell jar some pollen from a male flower together with, but …
Darwin in letters, 1864: Failing health
Summary
On receiving a photograph from Charles Darwin, the American botanist Asa Gray wrote on 11 July 1864: ‘the venerable beard gives the look of your having suffered, and … of having grown older’. Because of poor health, Because of poor health, Darwin…
Matches: 4 hits
- … whereby each form achieved the highest fertility only with pollen from the other two forms. The …
- … collecting and measuring flower parts, drawing pictures of pollen-grains, stigmas, and anthers, and …
- … writing on 14 April [1864] , ‘I can do as much pollen work as ever you like’. Comments on William’s …
- … Crüger confirmed both his observation of Catasetum pollen adhering to a humble-bee’s back, …
What is an experiment?
Summary
Darwin is not usually regarded as an experimenter, but rather as an astute observer and a grand theorist. His early career seems to confirm this. He began with detailed note-taking, collecting and cataloguing on the Beagle, and edited a descriptive zoology…
Darwin in letters, 1862: A multiplicity of experiments
Summary
1862 was a particularly productive year for Darwin. This was not only the case in his published output (two botanical papers and a book on the pollination mechanisms of orchids), but more particularly in the extent and breadth of the botanical experiments…
Species and varieties
Summary
On the origin of species by means of natural selection …so begins the title of Darwin’s most famous book, and the reader would rightly assume that such a thing as ‘species’ must therefore exist and be subject to description. But the title continues, …or…
Scientific Practice
Summary
Specialism|Experiment|Microscopes|Collecting|Theory Letter writing is often seen as a part of scientific communication, rather than as integral to knowledge making. This section shows how correspondence could help to shape the practice of science, from…
Matches: 1 hits
- … fertility of orchids he has self-pollinated and crossed with pollen of other species. …
Scientific Networks
Summary
Friendship|Mentors|Class|Gender In its broadest sense, a scientific network is a set of connections between people, places, and things that channel the communication of knowledge, and that substantially determine both its intellectual form and content,…
Matches: 3 hits
- … He discusses how dipterous insects are adapted to eating pollen rather than only to sucking nectar. …
- … flowers. One is ripening. Dissection of the other shows the pollen accomplishes fertilisation …
- … interpretation of Acropera pollination is ingenious. Pollen-tubes of some cleistogamous flowers …
Darwin in letters, 1877: Flowers and honours
Summary
Ever since the publication of Expression, Darwin’s research had centred firmly on botany. The year 1877 was no exception. The spring and early summer were spent completing Forms of flowers, his fifth book on a botanical topic. He then turned to the…
Matches: 4 hits
- … . ‘I will rank no plant as dimorphic without comparing pollen-grains & stigmas’, Darwin …
- … and painstaking measurements of the size and number of pollen-grains, Darwin compared the fertility …
- … especially with the aid of insects: the size and shape of pollen-grains, the position of stigmatic …
- … life to which all organisms are subjected, by producing both pollen and seeds’ ( Forms of flowers …
A tale of two bees
Summary
Darwinian evolution theory fundamentally changed the way we understand the environment and even led to the coining of the word 'ecology'. Darwin was fascinated by bees: he devised experiments to study the comb-building technique of honey bees and…
Matches: 1 hits
- … is, depressing the keel so that the mechanism which caused pollen to be deposited on the bee would …
