To M. T. Masters 25 April 1
Down Bromley Kent
My dear Sir
I beg you not to speak of “apologies for intruding”, when you are doing me the greatest kindness in giving me valuable information.2
I am heartily glad to hear of the papers in Linn: Journal, & then I shall see about peloria: I hope you will give any information which you may possess on the power of reproduction in peloria & other monsters.3 Of course you will naturally compare monstrous to normal structures: as far as I have seen, such comparisons have generally to be instituted between members of distinct groups, which to my mind greatly destroys the value of such parallelism in relation to the origin of species.4
Unless your Father5 actually experimentised on mixed pollen it is curious how he discovered the truth, which Gärtner has shown without doubt, namely that the stigma does select its own kind of pollen out of others; & more than that, for if the plant’s own pollen be put on stigma within a certain number (forgotten by me) of hours after foreign pollen, all influence from that foreign pollen is completely eliminated.6 But then no facts are known showing that this holds with the pollen of different varieties: on the contrary some facts lead to the suspicion that the pollen of a distinct variety has a prepotent effect over a plant’s own pollen.—7 In the case of Hollyhocks, I have suspected from some facts that each variety preferred its own pollen; & I have in vain been searching for information, from those who have raised many hollyhocks whether they found it necessary, in order to get the varieties pretty true by seed, to keep the several varieties in different parts of the garden. Has your Father raised with care, many seedling Hollyhocks.?8
I observe that your Father is a strong believer in the rule that when variation has once commenced it goes on.9
If at any time you were staying with your Father it would be a grand thing to get his reasons for this belief.—
That is a curious case about the yellow Hyacinths.10 The laws of inheritance seem to be determined to puzzle everyone.
With sincere thanks | My dear Sir | Yours sincerely | C. Darwin
Glad to hear of MTM’s papers [? "On a peloria and semidouble flower of Ophrys aranifera, Huds.", J. Linn. Soc. Lond. (Bot.) 8 (1865): 207–11 and "Observations on the morphology and anatomy of the genus Restio, Linn.", J. Linn. Soc. Lond. (Bot.) 8 (1865): 211–55].
CD doubts the value, for origin of species, of parallels between peloria in "distinct groups".
Gärtner proved the stigma can select its own pollen from a mixture of foreign pollens. But much evidence shows varieties of same species are prepotent over a plant’s own pollen.
MTM’s father [William] believes that variation goes on for a long time once it has commenced.
Please cite as
Darwin Correspondence Project, “Letter no. 4818,” accessed on 27 April 2017, http://www.darwinproject.ac.uk/DCP-LETT-4818
Also published in The Correspondence of Charles Darwin, vol. 13 (Supplement)