Ɛpsilon

To Francis Darwin   14 November [1881]1

Nov. 14th

My dear F.

The enclosed letter from Pfeffer is so nice & interesting one that I have thought that you wd like to see it—2 Please keep it— I am glad that he rejects the monstrous notion of Wiesner that the bits of card injure the tip of the root, & that this causes hypertrophy in the whole lower part on the same side.—3 I think Pfeffer must have written “Constellation” for “Constitution”.4

I am as yet not at all inclined to yield about Heliotropism being modified circumnutation.—5

By aid of Potash I have seen milk-tubes magnificently in germinating seeds of Euphorbiæ.—6

Your affec Father | C. D

1
The year is established by the relationship between this letter and the letter from Wilhelm Pfeffer, 6 November 1881.
2
CD enclosed the letter from Wilhelm Pfeffer, 6 November 1881; it contained remarks on Julius Wiesner’s study of plant movement (Wiesner 1881).
4
Pfeffer wrote ‘Constellationen’, meaning ‘combination of factors’.
6
CD was experimenting on the roots of Euphorbia (see letter to Francis Darwin, 9 November [1881] and n. 9). In a note dated 14 November, CD described the application of caustic potash (potassium hydroxide, KOH) to the roots of Euphorbia (DAR 62: 41).

Please cite as “DCP-LETT-13485,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13485