Packard attempted to incorporate cave fauna into a general theory of evolution that would be consistent with the principle of recapitulation, and would have as the primary mechanism the inheritance of the effects of the environment. Beyond this, he also attempted to demonstrate that the evolution of cave fauna was consistent with progressive evolution. The use he made of comparative anatomy and embryology places him within the tradition of classical morphology that was dominant through much of the last half of (...) the nineteenth century, but of waning importance by the time of Packard's death in 1905. The importance Packard gave to cave fauna as evidence for Lamarckian evolution stimulated interest in the phenomenon; this interest, and references to cave fauna in the scientific literature, declined after his death. Since then, the importance of cave fauna in evolutionary theory has declined from their status as the star evidence in Packard's theory to their present status as a difficult anomaly within the modern synthetic theory. (shrink)