From Hubert Airy 2 May 1876
Summary
On his new paper for Royal Society on a point of leaf arrangement. Asks CD to communicate it and "gives some details of its contents", e.g., recorded observations of changing leaf-order on individual specimens.
Comments on a paper by George Henslow ["Helianthus tuberosus", Trans. Linn. Soc. Lond. 26 (1876): 647].
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 2 May 1876 |
Classmark: | DAR 159: 30 |
Letter no: | DCP-LETT-10490 |
From Hubert Airy 3 April 1871
Summary
Comments on discussion of residual organs in Descent [ch. 1].
Describes his ability to contract the platysma myoides at will.
Suggests reason for loss of voluntary movement of ears in men and monkeys.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 3 Apr 1871 |
Classmark: | DAR 87: 37–8 |
Letter no: | DCP-LETT-7657 |
From Hubert Airy 9 December 1871
Summary
Reply to CD’s letter of 5 Apr 1871 [7659], in which he asked HA for further details on when and how platysma myoides contracts.
Replies to CD’s questions about sources on leaf arrangement.
Gives news of speech and paper about CD.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 9 Dec 1871 |
Classmark: | DAR 159: 13 |
Letter no: | DCP-LETT-8101 |
From Hubert Airy 12 December 1871
Summary
Thanks for letter and reference to Nägeli’s observations on leaf arrangement in the bud.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 12 Dec 1871 |
Classmark: | DAR 159: 14 |
Letter no: | DCP-LETT-8105 |
From Hubert Airy 31 May 1872
Summary
A review and criticism of Chauncey Wright’s paper on phyllotaxy [Mem. Am. Acad. Arts & Sci. n.s. 9 (1867–73): 379–415]. Does not believe that the "distributive" and "cyclical" properties, which CW claims characterise the existing spiral orders of leaf arrangement, can be shown to be advantageous to plants. CW’s speculations on the origins of the spiral arrangement of leaves are purely hypothetical.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 31 May 1872 |
Classmark: | DAR 159: 15 |
Letter no: | DCP-LETT-8362 |
From Hubert Airy 7 June 1872
Summary
On leaf arrangement. [Badly damaged and almost illegible.]
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 7 June 1872 |
Classmark: | DAR 159: 15a |
Letter no: | DCP-LETT-8372 |
From Hubert Airy [before 15] July 1872
Summary
Outlines his theory on the origin of existing orders of leaf arrangement. Believes spiral and whorled orders have evolved from a primitive distichous arrangement. These arrangements permit a compact bud form of small surface area that can withstand external changes in temperature, and in particular can tolerate frost.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | [before 15] July 1872 |
Classmark: | DAR 159: 16 |
Letter no: | DCP-LETT-8412 |
From Hubert Airy 16 July 1872
Summary
Thanks CD for reading his MS [8412] and for his suggestions.
Clarifies his statement on the contraction of the bud-axis: did not mean to imply that this contraction occurred in an individual’s life-time, rather that it was the effect, after the course of ages, of successive favourable modifications.
Believes the true theory of phyllotaxy will give a convincing illustration and proof of the theory of evolution.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 16 July 1872 |
Classmark: | DAR 159: 17 |
Letter no: | DCP-LETT-8414 |
From Hubert Airy 20 July 1872
Summary
Discusses the significance of the node. Believes, with CD, that it has no independent importance but is merely the consequence of the presence of a leaf. Does not believe a distinction can be made between whorled and alternate leaf arrangements on the basis of the number of leaves springing from a node. The node, as the starting point of a leaf, is subject to any disarrangement which takes place among the leaves.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 20 July 1872 |
Classmark: | DAR 159: 18 |
Letter no: | DCP-LETT-8418 |
From Hubert Airy 21 July 1872
Summary
Corrects a factual error in his previous letter [8418].
Sends specimens illustrative of the "nodal" question.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 21 July 1872 |
Classmark: | DAR 159: 19 |
Letter no: | DCP-LETT-8422 |
From Hubert Airy 24 July 1872
Summary
Responds to CD’s comments on his MS on phyllotaxy.
The initial variation required by his theory would be a slight twist of the bud-axis; believes the frequent twisting of stems and branches renders such a variation possible.
Admits he placed too much emphasis on the importance of frost. He should have spoken more generally of "vicissitudes of climate".
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 24 July 1872 |
Classmark: | DAR 159: 20 |
Letter no: | DCP-LETT-8426 |
From Hubert Airy 20 September 1872
Summary
Disputes Thomas Meehan’s observations on the hardiness of exposed buds, and believes bud-scales are for the protection of the bud-leaves. Reiterates his opinion that the phyllotaxy of a plant is determined by causes acting when the leaves are crowded into close contact. Attempts to explain how a different phyllotaxy on the upper and lower parts of the same shoot could have arisen.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 20 Sept 1872 |
Classmark: | DAR 159: 21 |
Letter no: | DCP-LETT-8527 |
From Hubert Airy 24 September 1872
Summary
Thanks for letter, in which CD cited [Anton] Kerner’s alpine observations.
Describes with diagrams the curious disposition of leaves on some Acacia twigs, and points out that his theory should account for these anomalies as well as normal cases.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 24 Sept 1872 |
Classmark: | DAR 159: 22 |
Letter no: | DCP-LETT-8532 |
From Hubert Airy 3 December 1872
Summary
Discusses works lent him by CD: Candolle, Kerner, Braun, Sachs, and CD’s own notes on relative positions of leaves. Plans paper on subject for Royal Society.
Just appointed medical inspector under local government board.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 3 Dec 1872 |
Classmark: | DAR 159: 23 |
Letter no: | DCP-LETT-8657 |
From Hubert Airy 3 January 1873
Summary
HA’s paper on leaf arrangement is almost ready; asks CD to communicate it to the Royal Society. Seeks permission to quote from CD’s notes.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 3 Jan 1873 |
Classmark: | DAR 159: 24 |
Letter no: | DCP-LETT-8720 |
From Hubert Airy 21 January 1873
Summary
Has sent phyllotaxy paper to G. G. Stokes with the letter from CD to show credentials.
Will not have time to read new Sachs edition CD offered.
Thanks for CD’s sponsorship of paper [Proc. R. Soc. Lond. 21 (1873): 176–9].
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 21 Jan 1873 |
Classmark: | DAR 159: 25 |
Letter no: | DCP-LETT-8745 |
From Hubert Airy 17 March 1873
Summary
Thanks for congratulations on appearance of abstract of HA’s paper [Nature 7 (1873): 343–4].
Explains again his theory of "contraction with twist" by which compact buds and a spiral phyllotaxy have evolved. Explains how the peculiar phyllotaxy of the teasel is explicable by this process of "condensation".
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 17 Mar 1873 |
Classmark: | DAR 159: 26 |
Letter no: | DCP-LETT-8812 |
From Hubert Airy 26 [September–November 1873]
Summary
The Royal Society referees have rejected HA’s phyllotaxy paper, and it will not be printed in Philosophical Transactions. HA is not sorry for he has found new facts which limit the applicability of his views. Now believes that the original leaf arrangement was not necessarily always two-ranked but rather that existing arrangements have developed from a variety of forms with differing numbers of leaf-ranks.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 26 [Sept-Nov] 1873 |
Classmark: | DAR 159: 31 |
Letter no: | DCP-LETT-9073 |
From Hubert Airy 7 December 1873
Summary
Illustrates, with reference to different species of Gasteria, the role of twisting in the development of leaf arrangement.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 7 Dec 1873 |
Classmark: | DAR 159: 27 |
Letter no: | DCP-LETT-9175 |
From Hubert Airy 8 January 1874
Summary
W. J. Beal’s paper ["Phyllotaxis of cones", Am. Nat. 7 (1873): 449–53] shows incompleteness of HA’s theory, but does not invalidate his basic principles on origin of leaf arrangement or the broad applicability of the theory.
Author: | Hubert Airy |
Addressee: | Charles Robert Darwin |
Date: | 8 Jan 1874 |
Classmark: | DAR 159: 28 |
Letter no: | DCP-LETT-9232 |