A subclass of Liliopsida (Monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, containing two orders (Bromeliales and Zingiberales), with nine families and about 3800 species. The subclass has been associated with the Commelinidae and the Liliidae, sharing some features with each but aberrant in either, and it differs from both in usually having four or more supporting cells around each stomate. The flowers are usually epigynous, usually bisexual, and often irregular, and they are usually showy and adapted to pollination by insects or other animals. The pistil consists of three united carpels, often with septal nectaries opening at the top of the ovary. The seeds usually have well-developed, mealy or starchy endosperm.