One of the most important natural historians in nineteenth century Britain, Charles Darwin provided the first compelling mechanism to account for organismal evolutionary change. Although lacking a coherent model of heredity, Darwin's natural selection has exerted an enormous influence over the biological sciences and since the introduction of Mendelian genetics, had remained the key unifying principle in the discipline. The APS Darwin Papers are a large a valuable assemblage of Darwin's correspondence with scientific colleagues, including Charles Lyell and George J. Romanes. They are included in the print version of the Correspondence of Charles Darwin (Cambridge Univ. Press).

Raymond Pearl spent the majority of his academic career (1918-1940) at Johns Hopkins University, where he was Professor of Biometry and Vital Statistics and Director of the Institute of Biological Research. Founder of the Quarterly Review of Biology and Human Biology, he made significant contributions in the areas of biology, genetics, eugenics, and statistics. The Pearl Papers includes correspondence as well as notebooks, scrapbooks, diplomas, photographs, and 33 volumes of diaries. There is significant correspondence with his wife, Maud (ca. 500 letters), and mother, Ida May (ca. 300 letters), particularly for the years 1895-1934. Of special note is Pearl's correspondence with his friend, colleague, and fellow Baltimoreian, H. L. Mencken (ca. 500 letters). The collection contains important information on the American Association of Physical Anthropologists, The Baltimore Sun, the Birth Control Federation of America, Dartmouth College, the International Institute of Statistics, Johns Hopkins University, and the National Academy of Sciences. This note is currently under review for revision.