The zodiacal symbol of Cancer appears in medieval Books of Hours as either a crab or a crayfish. Here the latter extends two elegant golden feelers beyond the quatrefoil frame (Timothy B. Husband, The Art of Illumination: The Limbourg Brothers and the Belles Heures of Jean de France, Duc de Berry, 2008). Teresa Pérez-Higuera (Medieval Calendars, 1998) deems it impossible either to establish the historical reasons or trace the iconographic models that lead to the choice of one crustacean over the other in medieval representations. She notes that the encyclopedist Saint Isidore, who can often be relied upon to provide a mythological explanation for the images used to designate the signs of the zodiac, confines himself to remarking that the motion of the sun in June (a month in which the days lengthen before the summer solstice and shorten after it) is mimicked by the “to-ing and fro-ing” of a crab.