Wax models of embryos and other biological specimens were widely used by anatomists in the latter half of the nineteenth century. Researchers produced their own three-dimensional models to help them understand the structures they observed, and commercially prepared models were widely used in teaching. Some of the finest and most widely used wax models, such as that of a human embryo in several pieces shown here, were produced by Adolf Ziegler, who trained as a doctor of medicine, and his son Friedrich. The Zieglers acted as 'wax publishers' for scientists such as Alexander Ecker, Ernst Haeckel and Wilhelm His. The history of the Ziegler models and their impact on embryological research is told in the lavishly illustrated book Embryos in Wax: Models from the Ziegler Studio by Nick Hopwood (Whipple Museum of the History of Sciences, University of Cambridge, and the Institute of the History of Medicine, University of Bern, £15).