Encourages JS to continue work on coloured primrose. No one has noticed this since Gärtner. CD will send his own data for JS's use and will read MS when ready. Advises JS to repeat experiments if evidence is weak – for his reputation's sake and for satisfaction at fully establishing a fact.
Treviranus made a slip of pen in writing of Primula longiflora as short-styled.
Down Bromley Kent
From what you say I looked again at Bot. Zeitung. Treviranus speaks of P. longiflora as short-styled, but this is evidently a slip of pen for further on, I see, he says the stigma always projects above anthers. Your experiments on coloured Primroses will be most valuable, if proved true: I will advise to best of my power when I see the M.S. If evidence is not good, I would recommend you, for your reputation sake, to try them again. It is not likely that you will be anticipated, & it is a great thing to fully establish, what in future time will be considered an important discovery (or rediscovery for no one has noticed G¨artners facts). I will procure coloured primroses, for next spring, but you may rely I will not publish before you.—
Do not work too hard to injure your health.—
I made some crosses between Primrose & Cowslip, & I send the results which you may use, if you like. But remember that I am not quite certain that I well castrated the short-styled Primrose; I believe any castration would be superfluous; as I find all plants sterile when insects are excluded.—
Be sure save seed of the crossed differently coloured Primroses or Cowslips which produced least seed to test the fertility of the quasi-hybrids. seedlings.— G¨artner found the common Primrose & Cowslip very difficult to cross, but he knew nothing on Dimorphism.—
I am sorry about delay on your orchid paper: I
There will be important paper in September in Annals & Mag. of
N. Hist, on ovules of orchids being formed months after application of pollen,
In Haste | Yours sincerely | C. Darwin
Are you sure that your coloured Primroses are not descendants of coloured Polyanthus; so as to be hybrids.—
This year I raised seedlings from wild oxlips, which had probably been naturally crossed with primroses; these seedlings closely resembled pure primroses, but the flower-peduncles rose from common scapes at the very crown of the plants, & so alone showed their parentage.
- f1 4253.f1The date is established by the relationship between this letter and the letter from John Scott, 23 July .
- f2 4253.f2See letter from John Scott, 23 July  and nn. 6 and 12. The reference is to Treviranus 1863a, pp. 4 and 5. There are annotated copies of the numbers of the Botanische Zeitung in which the paper appeared in the Darwin Pamphlet Collection--CUL.
- f3 4253.f3See letter from John Scott, 23 July . See also letter to John Scott, 1 and 3 August . CD received the draft manuscript of Scott 1864a in September, and sent his comments to Scott in November; however, his detailed criticisms have not been found (see letter from Emma Darwin to John Scott, 24 September , and letter to John Scott, 7 November ; see also Correspondence vol. 12, letter from John Scott, 7 January ). In introducing the results of his crosses between differently coloured varieties of the common primrose (Primula vulgaris), Scott observed: `Certain of these are so remarkable, that I hesitate not a little in bringing them forward until I have had again an opportunity of repeating my experiments' (Scott 1864a, p. 97).
- f4 4253.f4CD refers to the experiments carried out on Verbascum and Zea by Karl Friedrich von G¨artner, described in G¨artner 1844 and G¨artner 1849, in which crosses between differently coloured varieties of the same species produced less seed than the parallel crosses between similarly coloured varieties. There are very heavily annotated copies of these works in the Darwin Library--CUL (see Marginalia 1: 248--98). CD discussed the experiments in Origin pp. 270--1; he viewed them as important in countering a presumption against natural selection based on the belief that there is `some essential distinction between species and varieties' and that varieties `cross with perfect facility, and yield perfectly fertile offspring' (Origin, p. 268). On the reception of G¨artner's work, see Graepel 1978.
- f5 4253.f5Scott sent CD seed from his red and white varieties of primrose (Primula vulgaris) with his letter of [26 July -- 2 August 1863]. See also Correspondence vol. 12, letter from John Scott, 16 May . CD repeated Scott's experiments on a larger scale in 1865, with very different results (see letter to J. D. Hooker, 22 December , Calendar no. 4953; DAR 108: 89--98; DAR 110: 2--4; `Illegitimate offspring of dimorphic and trimorphic plants', pp. 420--3; and Variation 2: 109 n.).
- f6 4253.f6See letter from John Scott, 23 July  and n. 17. The enclosure has not been found; however, there are notes dated `July 1863' in DAR 108: 67--9, recording the results of CD's crossing experiments with cowslips and primroses. In addition, in reporting CD's results in Scott 1864a, pp. 103--4, Scott remarked in a footnote (p. 104 n.):
Mr. Darwin, in his letter to me accompanying the above results, remarks that the seeds of this short-styled Primrose were very small; so that we may perhaps suspect a number of them unfit for germination.
- f7 4253.f7Scott did not discuss the fertility of the plants grown from crosses between the differently coloured varieties of primroses or cowslips in Scott 1864a.
- f8 4253.f8G¨artner 1849, p. 721. See also Forms of flowers, pp. 58--9.
- f9 4253.f9See letter from John Scott, 23 July  and n. 19. The reference is to Scott 1863a.
- f10 4253.f10See letter from John Scott, 23 July .
- f11 4253.f11CD refers to Hildebrand 1863b, which appeared in the September 1863 issue of Annals and Magazine of Natural History (see preceding letter). Friedrich Hildebrand was a university lecturer at Bonn (Junker 1989).
- f12 4253.f12The postscript, which is written on a separate piece of paper, has been assigned to this letter on the basis of its relationship to the letters from John Scott, 23 July  and [26 July -- 2 August , and the letter to John Scott, 1 and 3 August .
- f13 4253.f13CD recorded this observation in his Experimental notebook (DAR 157a, pp. 75--7) on 10 April 1863; he reported it in `Specific difference in Primula', pp. 447--8. CD was interested in the commonly held view that common oxlips were the hybrid offspring of primroses and cowslips (see Correspondence vol. 10, letter to John Scott, 3 December  and nn. 13--15, and this volume, letter to John Scott, 25 and 28 May  and n. 11).