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.

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

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

Sends specimens illustrative of the "nodal" question.

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".