Samuel Haldeman was one of the only Americans, prior to 1859, to write about the process of evolution. Over his lifetime, he engaged in an extraordinarily diverse set of scholarly activities ranging from malacology to chess and philology. Early in his career, he performed geological survey work in New Jersey and Pennsylvania. Haldeman attended Dickinson College and eventually held academic positions at the Franklin Institute of Philadelphia, Delaware College, and the University of Pennsylvania. He wrote the first dictionary and analysis of the Pennsylvania Dutch language. In the mid 1840s, he published a paper, “Enumeration of the recent Freshwater Mollusca which Are Common to North American and Europe; With Observations on Species and their Distribution” in which he discussed the process of transmutation. Darwin read this paper and discussed it in correspondence with Charles Lyell (click here for letter) and Joseph Hooker (click here for letter).