FIGURES 1–4. 1. Friedrich Welwitsch. Photographer unknown. From Centro de Botânica/Instituto de Investigação Científica Tropical (IICT), Universidade de Lisboa. 2. Joaquim Silva (left) and José António surveying the mouth of Dande River in 1783. By José Antonio. Detail from Silva (post. 1785: fig. 84). © Arquivo Histórico dos Museus da Universidade de Lisboa. 3. Mary Pocock in a machila at Cuelei River, Angola, in 1925. Photographer unknown. Selmar Schonland Herbarium, Albany Museum, Grahamstown. 4. John Gossweiler. Photographer unknown. From Centro de Botânica/Instituto de Investigação Científica Tropical (IICT), Universidade de Lisboa. All reproduced with permission.