A mermaid is a mythological aquatic creature with a female human head and torso and the tail of a fish. Mermaids are represented broadly in folklore, literature, and popular culture. In Japan mermaids are called ningyo or 'fish people'. An old Japanese belief was that eating the flesh of a ningyo could grant immortality. Noted natural historian Baien Mouri (1798-1851), a prolific illustrator known for his colorful depictions of plants and animals, included two sketches of a mermaid in his 1835 book Baien Gyofu ('Baien Book of Fish').