[437] 'Teoria della Riproduzione Veg.,' 1816, p. 73.
[438] 'Bastarderzeugung,' s. 573.
[439] Ibid., s. 527.
[440] 'Transactions Phil. Soc.,' 1799, p. 202. For Kölreuter, see 'Mém. de l'Acad. de St. Pétersbourg,' tom. iii., 1809 (published 1811), p. 197. In reading C. K. Sprengel's remarkable work, 'Das entdeckte Geheimniss,' &c., 1793, it is curious to observe how often this wonderfully acute observer failed to understand the full meaning of the structure of the flowers which he has so well described, from not always having before his mind the key to the problem, namely, the good derived from the crossing of distinct individual plants.
[441] This abstract was published in the fourth edition (1866) of my 'Origin of Species;' but as this edition will be in the hands of but few persons, and as my original observations on this point have not as yet been published in detail, I have ventured here to reprint the abstract.
[442] The term unconscious selection has been objected to as a contradiction: but see some excellent observations on this head by Prof. Huxley ('Nat. Hist. Review,' Oct. 1864, p. 578), who remarks that when the wind heaps up sand-dunes it sifts and unconsciously selects from the gravel on the beach grains of sand of equal size.
[443] Sheep, 1838, p. 60.
[444] Mr. J. Wright on Shorthorn Cattle, in 'Journal of Royal Agricult. Soc.,' vol. vii. pp. 208, 209.
[445] H. D. Richardson on Pigs, 1817, p. 44.
[446] 'Journal of R. Agricult. Soc.,' vol. i. p. 24.