"Mad as a March hare" is a common British English phrase, both now and in Carroll's time, and appears in John Heywood's collection of proverbs published in 1546. It is reported in "The Annotated Alice" by Martin Gardner that this proverb is based on popular belief about hares' behaviour at the beginning of the long breeding season, which lasts from February to September in Britain. Early in the season, unreceptive females often use their forelegs to repel overenthusiastic males. It used to be incorrectly believed that these bouts were between males fighting for breeding supremacy.