This research will construct an historical case study of the model organism, Caenorhabditis elegans, in order to illuminate general philosophical and historical issues at the foundations of the biomedical sciences. Although there is a developing historical literature on factors governing organismal choice based on important case studies, little work has been done to trace historical and scientific factors surrounding the choice and development of the nematode Caenorhabditis elegans as a so-called model organism despite the prominence it has achieved as the focus of a highly successful research program. Further, biologists' use of the term `model organism` and its historical development and epistemological basis in biological practice has not been extensively explored. This project will examine the goals, motivations, and development of the `worm project` and the use of C. elegans as a model organism. Using this case study, a philosophical framework within which the epistemological dimensions of the use of model organisms in biology and medicine can be better understood will be developed.