It is not every one who is in a position to understand how great and momentous was the occasion when Sir Charles Lyell and Dr. Joseph Hooker communicated to the Linnean Society of London, on the 1st of July 1858, two papers, one by Charles Darwin, the other by Alfred Russel Wallace, under the common title, “On the Tendency of Species to form Varieties: and on the Perpetuation of Varieties and Species by Natural means of Selection.” The reason for this conjoint communication to the Linnean Society was that Darwin, who had been working for years at the subject, and had already, in 1842, drawn up a statement of his theory, not for publication, but for the consideration and criticism of his friend Hooker—unexpectedly received from Alfred Russel Wallace, who was, and had been for some years, away in the Malay Archipelago—a manuscript of an essay on the origin of species, containing views identical with his own, and even phrases similar to those he had himself found it necessary to invent. Thus Wallace speaks of the “struggle for existence,” whilst Darwin had used the term “struggle for life.” Darwin had been urged by his friends before this to publish an abstract or statement of his conclusions, but now that he had received Wallace’s manuscript, he declared in a letter to Hooker, “I would far rather burn my whole book than that he or any other man should think that I had behaved in a paltry spirit.” And so Lyell and Hooker took the matter in hand, and communicated to the Linnean Society, accompanied by an explanatory statement, the two independent papers, setting forth, as they say, “the results of the investigations of the indefatigable naturalists, Mr. Charles Darwin and Mr. Alfred Wallace.” Such loyalty and regard to each other as Darwin and Wallace showed then and ever after form a delightful feature in the history of this great discovery. A wonderful thing is that Hooker, now Sir Joseph Hooker, the greatest botanist of the past century, the constant friend and comrade of Darwin, is still alive, and that Alfred Russel Wallace, too, is still with us. They both were present when the Linnean Society celebrated the meeting of fifty years ago.