This thesis deals with the relationship between post Darwinian scientific thought and selected literary texts by Hardy, Gissing and H.G. Wells to illuminate the concept of degeneration and its implications for these writers in the period 1880-1910. It involves the examination of primary material in the field of biology, anthropology and medicine, as well as philosophical and social writing of the period and other related literary texts. Chapter One examines the major areas in emerges into biological, medical and cultural reflecting movements within scientific debate social, economic and philosophical concerns. this discussion is extended after 1900 and is light of Wells's own development. which degeneration discussion, itself and broader In chapter Four interpreted in the In the discussion of its biological and pathological emergence, the growth of hereditary determinism is particularly emphasised as crucial to the variety of applications of the concept. Degeneration reflects the prestige of Darwinian evolution, with its unresolved account of inheritance, a growing sense of economic decline, and a tension between the authority of evolutionary science and changing philosophical and ethical concerns. The three literary chapters deal with the impact of degeneration on the writers and illuminate aspects of their major work. While all the texts reflect the impact of degeneration, Gissing is revealed to be more dependent on scientific determinism, as in Demos or The Whirlpool, than is Hardy, who in Tess of the D'Urbervilles and Jude the Obscure, exposes the myth of that determinism while appearing to collude with it. Wells's journalism reflects the extent of his scientific endorsement of degeneration-producing in The Time Machine the one fiction about, and constructed around, it. The powerful conjunction of scientific ideas and imaginative writing, 1880-1910, can be traced to a perception of social, cultural and ethical crisis of the civilisation for which both novelist and scientist aspire to speak.