His life at Würtzburg was the most brilliant period of Virchow's indefatigable scientific labours. A change took place when he removed to Berlin in 1856. He then occupied himself chiefly with political and social and civic interests. In the last respect he has done so much for Berlin and the welfare of the German people that I need not enlarge on it. Nor will I go into his self-sacrificing and often thankless political work as leader of the progressive party; there are differences of opinion as to its value. But we must carefully examine his peculiar attitude towards evolution, and especially its chief application, the ape-theory. He was at first favourable to it, then sceptical, and finally decidedly hostile. When the Lamarckian theory was brought to light again by Darwin in 1859, many thought that it was Virchow's vocation to take the lead in defending it. He had made a thorough study of the problem of heredity; he had realised the power of adaptation through his study of pathological changes; and he had been directed to the great question of the origin of man by his anthropological studies. He was at that time regarded as a determined opponent of all dogmas; he combated transcendentalism either in the form of ecclesiastical creeds or anthropomorphism. After 1862 he declared that "the possibility of a transition from species to species was a necessity of science." When I opened the first public discussion of Darwinism at the Stettin scientific congress in 1863, Virchow and Alexander Braun were among the few scientists who would admit the subject to be important and deserving of the most careful study. When I sent to him in 1865 two lectures that I had delivered at Jena on the origin and genealogical tree of the human race, he willingly received them amongst his _Collection of Popular Scientific Lectures_. In the course of many long conversations I had with him on the matter, he agreed with me in the main, though with the prudent reserve and cool scepticism that characterised him. He adopts the same moderate attitude in the lecture that he delivered to the Artisans' Union at Berlin in 1869 on "Human and Ape Skulls."