To J. J. Weir 18 April 1
Down. | Bromley. | Kent. S.E.
My dear Sir
You see that I have taken you at yr word & have not (owin to heaps of stupid letters) earlier noticed your 3 last letters, which as usual are rich in facts.2 Your letters make almost a little volume on my table. I daresay you hardly knew yourself how much curious information was lying in yr mind till I began the severe pumping process.
The case of the starling, married thrice in one day is capital, and beats the case of the magpies of which one was shot seven times consecutively.3 A gamekeeper here tells me that he has repeatedly shot one of a pair of jays, and it has always been immediately replaced.4 I begin to think that the pairing of birds must be as delicate and tedious an operation as the pairing of young gentlemen and ladies. If I can convince myself that there are habitually many unpaired birds, it will be a great aid to me in sexual selection, about which I have lately had many troubles and am therefore rejoiced to hear in your last note that your faith keeps staunch.5 That is a curious fact about the bullfinches all appearing to listen to the German singer;6 and this leads me to ask how much faith may I put in the statement that male birds will sing in rivalry until they injure themselves. Yarrell7 formerly told me that they would sometimes even sing themselves to death. I am sorry to hear that the painted bullfinch turns out to be a female; tho’ she has done us a good turn in exhibiting her jealousy, of which I had no idea.8
Thank you for telling me about the wildness of the hybrid canaries: nothing has hardly ever surprised me more than the many cases of reversion from crossing.9 Do you not think it a very curious subject? I have not heard from Mr Bartlett about the Gallinaceæ, & I dare say I never shall.10 He told me about the Tragopan, & he is positive that the blue wattle become gorged with blood & not air.11
Returning to the first of the last 3 letters. It is most curious the number of persons of the name of Jenner who have had a strong taste for natural history. It is a pity you cannot trace your connection with the great Jenner, for a duke might be proud of his blood.12
I heard lately from Prof. Rolleston of the inherited effects of an injury in the same eye.13 Is the scar on yr son’s leg on the same side & on exactly the same spot, where you were wounded? and did the wound suppurate or heal by the first intention? I cannot persuade myself of the truth of the common belief of the influence of the mother’s imagination on the child.14
A point just occurs to me, (tho’ it does not at present concern me) about birds’ nests. Have you read Wallace’s recent articles?15 I always distrust myself when I differ from him; but I cannot admit that birds learn to make their nests from having seen them whilst young.16 I must think it as true an instinct as that which leads a caterpillar to suspend its cocoon in a particular manner— Have you had any experience of birds hatched under a foster-mother making their nests in the proper manner?
I cannot thank you enough for all yr kindness, & remain | my dear Sir | yours sincerely. | Ch. Darwin
Discusses rapid replacement of mates among birds. "I begin to think that the pairing of birds must be as delicate and tedious an operation as the pairing of young gentlemen and ladies. If I can convince myself that there are habitually many unpaired birds it will be a great aid to me in sexual selection". Notes rivalry of singing birds.
Heard from George Rolleston of the inherited effects of an eye injury.
Disagrees with A. R. Wallace’s idea "that birds learn to make their nests from having seen them whilst young" ["The philosophy of birds’ nests", Intellect. Obs. 11 (1867): 413–20].
Please cite as
Darwin Correspondence Project, “Letter no. 6128,” accessed on 9 December 2016, http://www.darwinproject.ac.uk/DCP-LETT-6128