Hummingbirds, from: Ernst Haeckel, Kunstformen der Natur, 1899-1904. (Trochilidae, Tafel 99)
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A first editon of the book by Ernst Haeckel, Kunstformen der Natur, 1899-1904, can be seen, on appointment, at the Special Collections of WUR Library (https://www.wur.nl/en/Library/Special-Collections.htm). This famous work had considerable influence on decorative design in the Jugendstil or Art Nouveau period in the beginning of the 20th century. It depicts fantastic, real forms and structures found in animal and plant life.