Annonaceae

Magnoliidae: Magnoliales: The Annonaceae are woody trees, shrubs and vines comprising about 130 genera and 2,300 species. The leaves are simple, alternate, lack stipules, and generally are distichously arranged in flat sprays. The flowers are bisexual and actinomorphic, possessing 3 whorls of perianth with 3 segments in each whorl. The elongated floral axis also bears many helically disposed stamens and several to many simple pistils. All of the floral parts are distinct. The stamens are very short, consisting of the fertile central anther portion, a distal pad of fleshy connective tissue, and a short fleshy basal portion. The stamens are generally so tightly packed on the receptacle that often only the fleshy connective tissue of each is exposed. The pistils each have a superior ovary with one locule and 1-many parietal ovules. Sectioned seeds reveal channels or partitions in the ruminate endosperm. The pistils generally remain distinct and develop into berry-like fruits but sometimes they coalesce into multiple fruits like the custard apple.

Each "thumbnail" image below is linked to a larger photograph.

	Cananga odorata, ylang ylang. Note the small greenish sepals alternating with the three outer petals and opposite the three inner petals. The cluster of fruit at the left is from a single flower.
	Artabotrys uncinatus, ylang ylang. Note three whorls of perianth, one of the inner petals has been removed to reveal the numerous greenish stamens and the yellowish pistils.
	Polyalthea suberosa. The trimerous nature of the perianth is apparent. The section through a seed reveals ruminate or compartmentalized endosperm and a small embryo.
	Annona muricata, soursop. Small tree from tropical America with edible, dark green, heart-shaped fruit covered with fleshy, curved, "prickles". The pulp makes a refreshing drink or "icee". The close-up of the flower reveals the inner two whorls of trimerous perianth and hundreds of tightly packed stamens forming a yellowish cup around the base of the central cluster of numerous tiny whitish pistils.

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