[99]

Shirref. Improvement of the Cereals. 1873. p 29. admits error of sterility of vars.

Refer to this book under Selection.

p. 47 Bud-sports in Wheat P

[Variation 2d ed. 1: 410: "My father repeatedly tried this experiment, and always with the same result. I may here mention that maize and wheat sometimes produce new varieties from the stock or root, as does the sugar-cane.72
72 For wheat, see 'Improvement of the Cereals,' by P. Shirreff, 1873, p. 47."]

p. 94. Crossing increases variability & gives greater room for selection

[Variation 2d ed. 1: 335: "Loiseleur-Deslongchamps45 has argued that, if our cereal plants have been greatly modified by cultivation, the weeds which habitually grow mingled with them would have been equally modified. But this argument shows how completely the principle of selection has been overlooked. That such weeds have not varied, or at least do not vary now in any extreme degree, is the opinion of Mr. H. C. Watson and Professor Asa Gray, as they inform me; but who will pretend to say that they do not vary as much as the individual plants of the same sub-variety of wheat? We have already seen that pure varieties of wheat, cultivated in the same field, offer many slight variations, which can be selected and separately propagated; and that occasionally more strongly pronounced variations appear, which, as Mr. Shirreff has proved, are well worthy of extensive cultivation.
45 'Les Céréales,' p. 94."]