A thesis submitted to the Faculty of Arts, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy / This thesis focuses on a selection of biographical treatments of Charles Darwin dating from 1887 to 1991, and through these explores certain shifts in the purposes and assumptions of biography since the Victorian period. An introductory discussion of problematic features in standard histories of biography is followed by an overview of the biographical material that surrounds Darwin. Four works are then analysed in detail. These are: The Life and Letters of Charles Darwin edited by his son Francis Darwin. (1887); Charles Darwin: The fragmentary man by Geoffrey West (1937); Darwin and the Beagle by Alan Moorehead (1969); and Darwin by Adrian Desmond and James Moore (1991). The disparities between these works - disparities in purpose, form, and the image of Darwin that each presents - are so great that one must question whether biography is a continuous, evolving family of texts. Is it not, rather, a conglomeration of approaches to life-writing - approaches which critics have grouped into a single genre much as the ancients grouped whales with fishes, on the basis that "because certain of their structural features are analogous, they must be generically-related"? The findings of this thesis do not supply a comprehensive answer, but affirm that we need to re-evaluate concepts like "the evolution of biography". In an appendix I analyse The Life of Richard Owen by R.S. Owen (1894) and thereby reconsider certain of my conclusions about Victorian biography. (Owen was the most eminent naturalist of the era and is often supposed to have been Darwin's greatest rival, hence my choice of this particular work.) / AC 2018