In the Book of Ezekiel and (at least some) Christian icons, the cherub is depicted as having a number of wing pairs, and four faces: that of a lion (representative of all wild animals), an ox (domestic animals), a human (humanity), and an eagle (birds). Their legs were straight, the soles of their feet like the hooves of a bull, gleaming like polished brass. Later tradition ascribes to them a variety of physical appearances. Some early midrashic literature conceives of them as non-corporeal. In Western Christian tradition, cherubim have become associated with the putto (derived from classical Cupid/Eros), resulting in depictions of cherubim as small, plump, winged boys.