[page] 781

The Effects of Cross and Self-Fertilisation in the Vegetable Kingdom.—The interest and value of this volume turns on the difference between crossed and self-fertilising plants, a crossed plant, seedling, or seed, meaning one crossed parentage, that is, one derived from a flower fertilised with pollen from a distinct plant of the same species. But a self-fertilising plant, seedling, or seed, means one of self-fertilised parentage, that is, one derived from a flower fertilised by pollen from the same flower, or sometimes from another flower on the same plant. The mere act of crossing, it appears, does no good in itself. The good depends on the individuals which are crossed differing slightly in their form and structure, owing to their progenitors having been subject during some generations to conditions slightly different, or to what, for want of a better name, is called spontaneous variation. There are sundry physiological problems of importance connected with this subject, such as the benefit derived from slight changes in the condition of life, and this stands in the closest connection with life itself. It throws light also on the origin of the two sexes and on their separation or union in the same individual, and on the whole matter of hybridism. Probably no one has ever investigated the vegetable kingdom so deeply as Mr. Darwin and he has, therefore, a right above all other men to be heard when speaking of those things to the study of which he has devoted his life.