The Foundations of the Origin of Species

242

See Var. under Dom., Ed. ii. vol. II. p. 230.

243

«Note in the original.» If domestic animals are descended from several species and become fertile inter se, then one can see they gain fertility by becoming adapted to new conditions and certainly domestic animals can withstand changes of climate without loss of fertility in an astonishing manner.

244

See Suchetet, L’Hybridité dans la Nature, Bruxelles, 1888, p. 67. In Var. under Dom., Ed. ii. vol. II. hybrids between the fowl and the pheasant are mentioned. I can give no information on the other cases.

245

Origin, Ed. i. p. 250, vi. p. 370.

246

This was the position of Gärtner and of Kölreuter: see Origin, Ed. i. pp. 246-7, vi. pp. 367-8.

247

«Note in the original.» Yet this seems introductory to the case of the heaths and crocuses above mentioned. «Herbert observed that crocus does not set seed if transplanted before pollination, but that such treatment after pollination has no sterilising effect. (Var. under Dom., Ed. ii. vol. II. p. 148.) On the same page is a mention of the Ericaceæ being subject to contabescence of the anthers. For Crinum see Origin, Ed. i. p. 250: for Rhododenron and Calceolaria see p. 251.»

248

«Note in original.» Animals seem more often made sterile by being taken out of their native condition than plants, and so are more sterile when crossed.

We have one broad fact that sterility in hybrids is not closely related to external difference, and these are what man alone gets by selection.

249

See Var. under Dom., Ed. ii. vol. II. p. 132; for the case of the cheetah see loc cit. p. 133.

250

Var. under Dom., Ed. ii. vol. II. p. 148.

251

Quoted in the Origin, Ed. i. p. 9.

252

See Var. under Dom., Ed. ii. vol. II. p. 147.

253

Var. under Dom., Ed. ii. vol. II. p. 89.

254

See Var. under Dom., Ed. ii. vol. II. p. 147.

255

Origin, Ed. i. p. 267, vi. p. 392. This is the principle experimentally investigated in the author’s Cross-and Self-Fertilisation.

256

Origin, Ed. i. p. 268, vi. p. 398.

257

«Notes in original.» Mere difference of structure no guide to what will or will not cross. First step gained by races keeping apart. «It is not clear where these notes were meant to go.»

258

Origin, Ed. i. p. 272, vi. p. 404.

259

This section seems not to correspond closely with any in the Origin, Ed. i.; in some points it resembles pp. 15, 16, also the section on analogous variation in distinct species, Origin, Ed. i. p. 159, vi. p. 194.

260

The law of compensation is discussed in the Origin, Ed. i. p. 147, vi. p. 182.

261

«Note in original.» Boitard and Corbié on outer edging red in tail of bird, – so bars on wing, white or black or brown, or white edged with black or «illegible»: analogous to marks running through genera but with different colours. Tail coloured in pigeons.

262

«Note in original.» Oxalis and Gentian. «In Gentians blue, yellow and reddish colours occur. In Oxalis yellow, purple, violet and pink.»

263

This section corresponds roughly to that on Hybrids and Mongrels compared independently of their fertility, Origin, Ed. i. p. 272, vi. p. 403. The discussion on Gärtner’s views, given in the Origin, is here wanting. The brief mention of prepotency is common to them both.

264

See Animals and Plants, Ed. ii. vol. I. p. 435. The phenomenon of Telegony, supposed to be established by this and similar cases, is now generally discredited in consequence of Ewart’s experiments.

265

The section on p. 109 (#Page_109) is an appendix to the summary.

266