The symbols of the evangelists derived from the Old Testament visions of Ezekiel and the vision of Saint John in the Apocalypse. In the West, the beasts of Saint John's vision are usually associated with the evangelists as follows: Matthew is represented by a man; Mark by a lion; Luke by a bull; and John by an eagle. The symbols may appear alone, either with attributes (wings, haloes, and books) or without ('terrestrial' symbols); they may identify accompanying Evangelist portraits; or they may be conflated with human figures to form zoo-anthropomorphic evangelist symbols.