Comparative embryos of hog, calf, rabbit and man from 'Anthropogenie, oder, Entwickelungsgeschichte des Menschen: Keimes- und Stammes-Geschichte' by Ernst Haeckel.
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: Comparative embryos of hog, calf, rabbit and man from 'Anthropogenie, oder, Entwickelungsgeschichte des Menschen: Keimes- und Stammes-Geschichte' by Ernst Haeckel. Wellcome Collection. Source: Wellcome Collection.