James Elwick explores how the concept of 'compound individuality' brought together life scientists working in pre-Darwinian London. Scientists conducting research in comparative anatomy, physiology, cellular microscopy, embryology and the neurosciences repeatedly stated that plants and animals were compounds of smaller independent units. Discussion of a 'bodily oeconomy" was widespread. But by 1860 the most flamboyant discussions of compound individuality had come to an end in Britain.<BR>Elwick relates the growth and decline of questions about compound individuality to wider nineteenth-century debates about research standards and causality. He uses specific technical case studies to address overarching themes of reason and scientific method.