AT the annual conference of the School Nature Study Union, held in January, Prof. E. W. MacBride was the speaker, and his address upon “The All-importance of the Study of Habits for the Knowledge of Evolution“was, in effect, a statement of his evolutionary faith (School Nature Study, 1935, p. 2). He led to his own viewpoint by a vigorous onslaught upon the faiths of others. Evolution we all accept, but the way thereof is dark. Darwin, we learn, with his natural selection of variations, was a false prophet, for natural selection does not work even if small deviations were heritable, which they are not. The mutationists are equally in error, for a mutation is a suddenly produced disturbance of development which persists only so long as the conditions producing it continue. According to Prof. MacBride, the truth lies with the neo-Lamarckians in their belief that use and disuse, in short habit, have been the mainspring of the progress of evolution. “Habit long persisted in does affect posterity and is the driving force in evolution; the personality, if we may use such a word, of a living being, is made up of a complex of inherited habits, and habits deeply ingrained are extraordinarily persistent.“Prof. MacBride supports his thesis and trounces his opponents by quoting experimental results well selected for his purpose. Thirty years ago 110 biologist would have listened to the Lamarckian view; nowadays we are not so sure.