When “Life and Habit” was first published no one considered Mr. Spencer to be maintaining the phenomena of heredity to be in reality phenomena of memory. When, for example, Professor Ray Lankester first called attention to Professor Hering’s address, he did not understand Mr. Spencer to be intending this. “Professor Hering,” he wrote (_Nature_, July 13, 1876), “helps us to a comprehensive view of the nature of heredity and adaptation, by giving us the word ‘memory,’ conscious or unconscious, for the continuity of Mr. Spencer’s polar forces or polarities of physiological units.” He evidently found the prominence given to memory a help to him which he had not derived from reading Mr. Spencer’s works. When, again, he attacked me in the _Athenæum_ (March 29, 1884), he spoke of my “tardy recognition” of the fact that Professor Hering had preceded me “in treating all manifestations of heredity as a form of memory.” Professor Lankester’s words could have no force if he held that any other writer, and much less so well known a writer as Mr. Spencer, had preceded me in putting forward the theory in question. When Mr. Romanes reviewed “Unconscious Memory” in _Nature_ (January 27, 1881) the notion of a “race-memory,” to use his own words, was still so new to him that he declared it “simply absurd” to suppose that it could “possibly be fraught with any benefit to science,” and with him too it was Professor Hering who had anticipated me in the matter, not Mr. Spencer. In his “Mental Evolution in Animals” (p. 296) he said that Canon Kingsley, writing in 1867, was the first to advance the theory that instinct is inherited memory; he could not have said this if Mr. Spencer had been understood to have been upholding this view for the last thirty years. Mr. A. R. Wallace reviewed “Life and Habit” in _Nature_ (March 27, 1879), but he did not find the line I had taken a familiar one, as he surely must have done if it had followed easily by implication from Mr. Spencer’s works. He called it “an ingenious and paradoxical explanation” which was evidently new to him. He concluded by saying that “it might yet afford a clue to some of the deepest mysteries of the organic world.” Professor Mivart, when he reviewed my books on Evolution in the _American Catholic Quarterly Review_ (July 1881), said, “Mr Butler is not only perfectly logical and consistent in the startling consequences he deduces from his principles, but,” &c. Professor Mivart could not have found my consequences startling if they had already been insisted upon for many years by one of the best-known writers of the day.