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peas—not precisely the laws Professor Weldon has been at the pains of drafting, but of that anon. Having done so, he knew what his discovery was worth. He saw, and rightly, that he had found a principle which must govern a wide area of phenomena. He entitles his paper therefore "Versuche über Pflanzen-Hybriden," or, Experiments in Plant-Hybridisation.

Nor did Mendel start at first with any particular intention respecting Peas. He tells us himself that he wanted to find the laws of inheritance in hybrids, which he suspected were definite, and that after casting about for a suitable subject, he found one in peas, for the reasons he sets out.

In another respect the question of title is much more important. By the introduction of the word "Alternative" the suggestion is made that the Mendelian principle applies peculiarly to cases of "alternative" inheritance. Mendel himself makes no such limitation in his earlier paper, though perhaps by rather remote implication in the second, to which the reader should have been referred. On the contrary, he wisely abstains from prejudicial consideration of unexplored phenomena.

To understand the significance of the word "alternative" as introduced by Professor Weldon we must go back a little in the history of these studies. In the year 1897 Galton formally announced the Law of Ancestral Heredity referred to in the Introduction, having previously "stated it briefly and with hesitation" in Natural Inheritance, p. 134. In 1898 Professor Pearson published his modification and generalisation of Galton's Law, introducing a correction of admitted theoretical importance, though it is not in question that the principle thus restated is funda-