The Codex Seraphinianus,[1] originally published in 1981, is an illustrated encyclopedia of an imaginary world, created by Italian artist, architect and industrial designer Luigi Serafini between 1976 and 1978.

[3] The Codex is an encyclopedia in manuscript with copious hand-drawn, colored-pencil illustrations of bizarre and fantastical flora, fauna, anatomies, fashions, and foods.

[4] It has been compared to the still undeciphered Voynich manuscript,[5] the story "Tlön, Uqbar, Orbis Tertius" by Jorge Luis Borges,[6] and the artwork of M. C. Escher[7] and Hieronymus Bosch.

[3][4] The illustrations are often surreal[4][7][8] parodies of things in the real world, such as a bleeding fruit, a plant that grows into roughly the shape of a chair and is subsequently made into one, and a copulating couple who metamorphose into an alligator.

[10] However, the book's page-numbering system was decoded by Allan C. Wechsler[11] and Bulgarian linguist Ivan Derzhanski,[12] as being a variation of base 21.