Summary

Thanks for letter and reference to Nägeli’s observations on leaf arrangement in the bud.

Summary

On leaf arrangement. [Badly damaged and almost illegible.]

Summary

Agrees to read paper; warns he lacks mathematical knowledge.

Summary

Sends HA’s paper ["On leaf arrangement"] with a supporting note [from CD] to Royal Society.

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.

Summary

Corrects a factual error in his previous letter [8418].

Sends specimens illustrative of the "nodal" question.

Summary

Agrees to aid HA in applying for membership in a society.

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.

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.

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].

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.

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.

Summary

Discusses loss of voluntary movement of ears in man and monkey.

Summary

CD’s son Leonard of the Royal Engineers has applied to Sir George Biddell Airy to be an observer on the Venus Expedition. Leonard failed to mention his qualifications, which CD now relates with the request that HA draw them to his father’s attention.

Summary

Discusses movement of ears and contraction of the platysma.

Discusses phyllotaxy, citing work of Carl Nägeli and Chauncey Wright.

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.

Summary

Illustrates, with reference to different species of Gasteria, the role of twisting in the development of leaf arrangement.

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".

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.

Summary

Has rewritten paper on leaf arrangement after criticism by Royal Society referees. Has found new factor influencing leaf arrangement, i.e., spontaneous variability in the number of vertical leaf-ranks.