Flowers subtended by a primary bract and 2 bracteoles, sessile, usually 4-merous, minute, lowermost ones female, uppermost ones male, sometimes middle ones bisexual.

• 花具一原生苞片和2小苞片，无梗，4瓣，雌花的小，最下，雄花的最上的通常被包着，雄花：花萼2-4深裂；