“This image from Ernst Haeckel’s 1874 The Evolution of Man shows comparisons between cross-sections of different animals and their embryos at different stages of development. For Haeckel the development of an embryo retraced the evolutionary history of the animal. The different colors represent the four types of tissues out of which all the organs formed. Ernst Haeckel. Anthropogenie, oder, Entwickelungsgeschichte des Menschen. Leipzig: W. Engelmann. 1874.” – link

“Title: Outlines of Comparative Physiology
Maker: Louis Agassiz, 1851
Significance: In opposition to Darwin” – link

“Nott, Types of Mankind
Here American physician J. C. Nott attempted to illustrate geologist Louis Agassiz’s theory, which was that each region of the world was populated by separately created sets of species, both animal and human. Such ideas about human species at the time were often influenced by western racial prejudices, as the idea of multiple, separately created races could be used to justify slavery and other forms of subjugation. Darwin disagreed, firmly maintaining that all humans were descended from the same human ancestor. Josiah Clark Nott (1804–1873). Types of Mankind…. Philadelphia: Lippincott and Grambo, 1854.” – link

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