To W. C. Tait   17 July [1869]¹

My dear Sir

Your obliging letter of the 11th has been forwarded to me here.² The case of the Geranium is not new; there are many plants, often called Dichogamous, in which the anthers shed their pollen before the stigma is ready, and a few converse cases in which the stigma is mature before the pollen is ready. All these dichogams absolutely require cross-fertilisation. When I left home a month ago one alone of the Drosophyllums was still healthy.³ D^r Hooker⁴ begins to have some doubts whether Drosophyllum is so closely allied to Drosera. Pray do not give yourself any more trouble about the development of the Horns in Sheep. I have acquired some facts from Saxony which must suffice.⁵

I am not intending at present to publish on Instinct, though I have much MS. almost ready for press;⁶ and I doubt whether my strength will last out to publish much more on any subject. We have taken this house for 8 weeks for change of air, but it has done me very little good, and I hope to be at home again by the end of this month.

Pray believe me, | My dear Sir, | Yours very faithfully | Ch. Darwin

[…]

P.S. 2^d [Asks whether Tait saw CD’s] little Book on the Fertilisation of Orchids by Insect Agency [and offers to send him a copy.]⁷