From Friedrich Hildebrand 10 November 1863
Novbr 10th | 1863
Dear and respected Sir
I must beg your pardon that I have not answered your very kind letter before this, but I was waiting for my paper on Orchids being printed in the Botanische Zeitung to send you a copy;1 I hope that I shall be able to do it in the next days, you will see that it does not contain much more as you know as yet from my last letter.2 And now let me thank you that you have taken so much pain to get my paper printed, I have seen it in the Annals and Mag. of n. hist. and was very glad of it; I feel very much obliged to you.3 I am glad being able to do you a service in publishing my experiments on Linum and Primula, but I can speak only about L. perenne and P. sinensis, beacause my experiments on P. officinalis and elatior were destroyed by childeren in the botanical garden.4 On Linum I spoke a few words on the meeting of German naturalists in Stettin.5
In your paper on Primula you say, that you never placed pollen of the same flower on its own stigma6 but I thought this manner of fertilisation to be of interest too, and I had in this way six unions instead of your four. The result was that the two heteromorphic unions gave most seeds, namely each capsule 43 good seeds on an average; the two homomorphic unions, if the flowers were crossed, gave 18 seeds on an average per capsule, the flowers selffertilised only 13. In the first four unions I got good capsules of every fertilised flower, only in the last two I did not always succeed in the fertilisation.— You see that, though I have counted the seeds, not weighed, I have come to the same results as you.7 But I must say that I cannot agree with you about the pollen of P. sinensis, for I found the pollen grains of the long styled form almost in the same manner differing from that of the short styled as in P. officinalis and elatior; between the small transparent grains of the short-styled form there were only a few of larger seize and opace.—8
Perhaps it will interest you to hear that I have made other experiments to answer the question to what form the descendants of the two forms belong. From seeds that I had got last year by your four unions I got about 60 young plants and these were the interesting results: Of the descendants from long-styled plants fertilised with their own form pollen most, but not all, were again long styled; the short-styled form fertilised with its own-form pollen produced in the greatest part short styled plants; if the short styled form was fertilised with the long-styled or the long styled with the short styled nearly the half of the young plants was short-styled the other half long-styled.—9
Coming to a close I must say that if there is anything, where I can serve you, perhaps with microscopical researches, I should be very glad if you would tell me about it, the winter especially leaves me a great deal of time.
Professor Treviranus wanted me to send you his respects and remembrances.10 Some time ago I heard that you were not quite well but I hope that this letter will find you in good health and I remain most respected Sir | yours | sincerely | Hildebrand
Pleased CD has had his [FH’s] orchid paper published [Ann. & Mag. Nat. Hist. 3d ser. 12 (1863): 169–74].
Extension of CD’s Primula heterostyly work.
Please cite as
Darwin Correspondence Project, “Letter no. 4337,” accessed on 22 October 2016, http://www.darwinproject.ac.uk/DCP-LETT-4337