A West African representative of the group of monkeys generally known as guenons, and scientifically as Cercopithecus. The mona ( C. mona ) typifies a sub-genus of the same name (Mona ) characterized, among other features, by the presence of a black band running from the angle of each eye to the ear. In the mona itself the general colour of the upper parts is black, with a pair of oval white spots near the root of the tail, while a band across the forehead and the whole under surface are likewise white. (See PRIMATES.)