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marginalia

Drolleries were common in medieval manuscripts.

Drolleries of the Middle Ages Included Comical Yet Sinister Killer Rabbits and Erotic Art

A drollerie (also spelled as drollery) is a type of marginalia found on Medieval manuscripts. Drolleries are amusing, often grotesque, figures drawn on the edges of manuscripts and may be found in...
Opening from the Hours of Catherine of Cleves, 1440. The Morgan Library & Museum.

Beautiful, Decorative, and Sometimes Crude: Illuminated Manuscripts and Marginalia

Illuminated manuscripts are manuscripts that are covered with painted ornaments presented under several forms. These documents are perhaps most commonly associated with the European Middle Ages...