Ɛpsilon

To Camilla Pattrick   [after 6 November 1881]1

[Down.]

It is of much importance to me to know what Pfeffer means in relation to Wiesners book who has just published a book vivisecting me in the most courteous manner.2

Wiesner looks at Light causing a plant to bend towards it as a direct effect, as much as the lengthening of a bar of iron by heat. I maintain that the light acts as a stimulus & merely tells the plant which way to bend.—3

I thought that Pfeffer was on Wiesner’s side, & I am sure that he was so formerly.— I have written this, because I thought that it would help Mr Patrick4 & yourself in understanding Pfeffers notoriously difficult (to Germans) style

C. D.

incomplete

1
The date 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, to be translated from the German; it contained remarks on Julius Wiesner’s critique of CD’s work on plant movement (Wiesner 1881). Pfeffer agreed with CD’s interpretation that the effect of light was one of stimulus-response.
3
CD discussed his views on light as a stimulus to plant movement in his letter to Julius Wiesner, 25 October 1881; see also Movement in plants, pp. 565–7.

Manuscript Alterations and Comments

1.2 just] interl
2.2 a stimulus 2.3] ‘a’ interl

Please cite as “DCP-LETT-13447,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13447