In the decades around 1800, many people were interested in understanding the way in which complex bodies develop from simple beginnings. Wax models from the La Specola museum in Florence, Italy, are based on the idea that the initial 'germ' was already fully formed, and only needed to grow during pregnancy. (This is known as the preformist concept of development.)
It was difficult to obtain specimens of embryos, especially for the early stages of development and museums and research institutes were proud of their embryo collections. Institutions attempted to safeguard these precious specimens by preserving them in spirits and also by making models as copies.
Embryos and evolution
In the 19th century, embryology became increasingly important, since the study of embryo development was seen as a way to investigate laws of organic development more generally. Interest in this subject was fuelled by Darwin's theory of evolution, published in 1859 in The Origin of Species. One of Darwin's followers, the German biologist Ernst Haeckel (1834-1919), even proposed that embryo development reflected evolutionary development.