Polycarpaea  

  ♦ Polycarpaea Lamarck, J. Hist. Nat. 2: 3, 5. 1792.
bai gu ding shu. Lu Dequan; Michael G. Gilbert

Herbs or subshrubs, annual or perennial. Stems erect or diffuse. Leaves opposite or falsely verticillate with axillary clusters of leaves, sessile or petiolate; leaf blade linear to obovate; stipules membranous or hyaline. Inflorescence a cyme, terminal. Flowers numerous, 5-merous. Sepals hyaline, midvein not raised. Petals usually small, entire or 2-lobed. Stamens (2--)5. Ovary 1-loculed with few to many ovules; style undivided at apex. Fruit a capsule, 3-valved, few to several seeded. Seeds reniform, slightly flat.