This article uses the work of Anna Semper (1826–1909) to explore the possibilities for understanding women’s contributions to the development of science in Germany from the second half of the 19th century to the beginning of the 20th century. By examining the publications of her husband, the naturalist Carl Semper (1832–1893), as well as those of other scholars, traces of the ways that she produced scientific knowledge begin to emerge. Because the Sempers’ work took place in the context of the Philippines and Palau, two different Spanish colonies, and formed the basis of Carl’s professional career, this article also analyzes Anna’s role in the creation of an explicitly colonial science.