Mistletoe
A man should pluck a berry when he kisses a woman under the mistletoe. When the last berry is gone, there should be no more kissing. A health to mistletoe and a Merry Christmas!
Here were kept up the old games of hoodman blind, shoe the wild mare, hot cockles, steal the white loaf, bob apple, and snap dragon; the Yule-clog and Christmas candle were regularly burnt, and the mistletoe with its white berries hung up, to the imminent peril of all the pretty housemaids. – Washington Irving,The Sketch Book of Geoffrey Crayon, Gent, Christmas Eve.