Until recently the British zoologist Lancelot Hogben has usually appeared as a campaigning socialist, an anti-eugenicist or a popularizer of science in the literature. The focus has mainly been on Hogben after he became a professor of social biology at the London School of Economics in 1930. This paper focuses on Hogben’s life in the 1920s. Early in the decade, while based in London, he focused on cytology, but in 1922, after moving to Edinburgh, he turned his focus on experimental (...) zoology, first concentrating on vertebrate endocrinology and later moving over to the comparative physiology of invertebrate muscle. In the early 1920s Hogben played an active role in the development of experimental zoology in Britain. As such he was a fearless critic of evolutionary and metaphysical speculations. But in this period Hogben’s career prospects were seriously hampered by his confrontational nature and serious depression. As a result he was forced to leave Britain in 1925. He first accepted a position in Canada and in the period 1927–1930 he was a professor of zoology in South Africa. This paper will also add crucial new material to James Tabery’s recent discussion of the history behind Hogben’s ideas about the interaction of heredity and environment in individual development. In addition a previously unknown Lamarckian controversy will be discussed. (shrink)