By superficial appearance , Old World monkeys are unlike apes in that most have tails ( the family name means `` tailed ape '' ) , and unlike the New World monkeys ( platyrrhines ) in that their tails are never prehensile .
By appearance , Old World monkeys are unlike apes in that most have tails ( the family name means `` tailed ape '' ) , and unlike the New World monkeys in that their tails are never prehensile ( used for holding on ) .