Between 1880 and 1950, women entered American natural history institutions significant numbers. In herbaria, natural history museums, arboreta, botanical gardens, and related institutions, women participated as patrons, curators, volunteers, club members, and in other significant roles. In fact, women managed collections and held high-ranking curatorial positions for several decades at institutions across the United States. However, despite their success, these women's contributions are largely absent from the historiography of science and completely absent from science studies scholarship. This dissertation does not merely recuperate and celebrate their lives, but rather uncovers patterns and discontinuities in their experiences as naturalists. Their experiences, taken collectively, provide us with a new context in which to comprehend the processes by which people cane to understand varieties of "science" and the dissemination of scientific knowledge at the end of the nineteenth and during the first half of the twentieth century. These women found themselves ensconced in a matrix not only of research scientists, but of interested laypeople and supporters. Their founding of and participation in a broad spectrum of organizations provided the women with new spaces to showcase their expertise and, by extension, to recruit more women to pursue or otherwise support natural science. Although most of the scientists discussed in this study were successful when measured by the standards of their disciplines, I argue that their greatest long-term contributions to science may have occurred outside the walls of their institutions. These women's disciplinary contributions are eclipsed by their success in democratizing science through outreach activities. In spaces outside the museum, the women were allowed to experiment with the full range of their humanity, acting as both women and scientists in ways they may not have been allowed to do so inside their museums. In their lasting contributions to science---namely in their dedication to increasing the public understanding of science---women scientists were often more successful as women scientists rather than as women scientists .