The Variation of Animals and Plants Under Domestication, Volume II (of 2). Darwin Charles

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Название The Variation of Animals and Plants Under Domestication, Volume II (of 2)
Автор произведения Darwin Charles
Жанр Зарубежная классика
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Издательство Зарубежная классика
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s. 216.

229

The following facts, given by Kölreuter in his 'Dritte Fortsetzung,' s. 34, 39, appear at first sight strongly to confirm Mr. Scott's and Gärtner's statements; and to a certain limited extent they do so. Kölreuter asserts, from innumerable observations, that insects incessantly carry pollen from one species and variety of Verbascum to another; and I can confirm this assertion; yet he found that the white and yellow varieties of Verbascum lychnitis often grew wild mingled together: moreover, he cultivated these two varieties in considerable numbers during four years in his garden, and they kept true by seed; but when he crossed them, they produced flowers of an intermediate tint. Hence it might have thought that both varieties must have a stronger elective affinity for the pollen of their own variety than for that of the other; this elective affinity, I may add, of each species for its own pollen (Kölreuter, 'Dritte Forts.,' s. 39, and Gärtner, 'Bastarderz.,' passim) being a perfectly well-ascertained power. But the force of the foregoing facts is much lessened by Gärtner's numerous experiments, for, differently from Kölreuter, he never once got ('Bastarderz.,' s. 307) an intermediate tint when he crossed the yellow and white flowered varieties of Verbascum. So that the fact of the white and yellow varieties keeping true to their colour by seed does not prove that they were not mutually fertilised by the pollen carried by insects from one to the other.

230

'Amaryllidaceæ,' 1837, p. 366. Gärtner has made a similar observation.

231

Kölreuter first observed this fact. 'Mém. de l'Acad. St. Petersburg,' vol. iii. p. 197. See also C. K. Sprengel, 'Das Entdeckte Geheimniss,' s. 345.

232

Namely, Barbarines, Pastissons, Giraumous: 'Annal. des Sc. Nat.,' tom. xxx., 1833, pp. 398 and 405.

233

'Mémoire sur les Cucurbitaceæ,' 1826, pp. 46, 55.

234

'Annales des Se. Nat.,' 4th series, tom. vi. M. Naudin considers these forms as undoubtedly varieties of Cucurbita pepo.

235

'Mém. Cucurb.,' p. 8.

236

'Zweite Forts.,' s. 53, namely, Nicotiana major vulgaris; (2) perennis; (3) Transylvanica; (4) a sub-var. of the last; (5) major latifol. fl. alb.

237

Kölreuter was so much struck with this fact that he suspected that a little pollen of N. glutinosa in one of his experiments might have accidentally got mingled with that of var. perennis, and thus aided its fertilising power. But we now know conclusively from Gärtner ('Bastarderz.,' s. 34, 431) that two kinds of pollen never act conjointly on a third species; still less will the pollen of a distinct species, mingled with a plant's own pollen, if the latter be present in sufficient quantity, have any effect. The sole effect of mingling two kinds of pollen is to produce in the same capsule seeds which yield plants, some taking after the one and some after the other parent.

238

Mr. Scott has made some observations on the absolute sterility of a purple and white primrose (Primula vulgaris) when fertilised by pollen from the primrose ('Journal of Proc. of Linn. Soc.,' vol. viii., 1864, p. 98); but these observations require confirmation. I raised a number of purple-flowered long-styled seedlings from seed kindly sent me by Mr. Scott, and, though they were all some degree sterile, they were much more fertile with pollen taken from the common primrose than with their own pollen. Mr. Scott has likewise described a red equal-styled cowslip (P. veris, idem, p. 106), which was found by him to be highly sterile when crossed with the common cowslip; but this was not the case with several equal-styled red seedlings raised by me from his plant. This variety of the cowslip presents the remarkable peculiarity of combining male organs in every respect like those of the short-styled form, with female organs resembling in function and partly in structure those of the long-styled form; so that we have the singular anomaly of the two forms combined in the same flower. Hence it is not surprising that these flowers should be spontaneously self-infertile in a high degree.

239

'Act. Acad. St. Petersburg,' 1780, part ii., pp. 84, 100.

240

'Annales des Sc. Nat.,' tom. xxi. (1st series), p. 61.

241

'Bull. Bot. Soc. de France,' Dec. 27th, 1861, tom. viii. p. 612.

242

Quoted by Isid. Geoffroy St. Hilaire, 'Hist. Naturelle Générale,' tom. iii. p. 476. Since this MS. has been sent to press a full discussion on the present subject has appeared in Mr. Herbert Spencer's 'Principles of Biology,' vol. ii. 1867, p. 457 et seq.

243

For cats and dogs, &c., see Bellingeri, in 'Annal. des Sc. Nat.,' 2nd series, Zoolog., tom. xii. p. 155. For ferrets, Bechstein, 'Naturgeschichte Deutschlands,' Band i., 1801, s. 786, 795. For rabbits, ditto, s. 1123, 1131; and Bronn's 'Geschichte der Natur,' B. ii. s. 99. For mountain sheep, ditto, s. 102. For the fertility of the wild sow, see Bechstein's 'Naturgesch. Deutschlands,' B. i., 1801, s. 534; for the domestic pig, Sidney's edit. of Youatt on the Pig, 1860, p. 62. With respect to Lapland, see Acerbi's 'Travels to the North Cape,' Eng. translat., vol. ii. p. 222. About the Highland cows, see Hogg on Sheep, p. 263.

244

For the eggs of Gallus bankiva, see Blyth, in 'Annals and Mag. of Nat. Hist., 2nd series, vol. i., 1848, p. 456. For wild and tame ducks, Macgillivray, 'British Birds,' vol. v. p. 37; and 'Die Enten,' s. 87. For wild geese, L. Lloyd, 'Scandinavian Adventures,' vol. ii. 1854, p. 413; and for tame geese, 'Ornamental Poultry,' by Rev. E. S. Dixon, p. 139. On the breeding of pigeons, Pistor, 'Das Ganze der Taubenzucht,' 1831, s. 46; and Boitard and Corbié, 'Les Pigeons,' p. 158. With respect to peacocks, according to Temminck ('Hist. Nat. Gén. des Pigeons,' &c., 1813, tom. ii. p. 41), the hen lays in India even as many as twenty eggs; but according to Jerdon and another writer (quoted in Tegetmeier's 'Poultry Book,' 1866, pp. 280, 282), she there lays only from four to nine or ten eggs: in England she is said, in the 'Poultry Book,' to lay five or six, but another writer says from eight to twelve eggs.

245

'The Art of Improving the Breed, &c.,' 1809, p. 16.

246

For Andrew Knight, see A. Walker, on 'Intermarriage,' 1838, p. 227. Sir J. Sebright's Treatise has just been quoted.