Deciduous shrubs with opposite undivided entire exstipulate leaves and solitary axillary often fragrant or aromatic flowers. Sepals and petals in many series, the outermost small and bract-like, the inner petaloid, inserted on the outside of a fleshy urceolate torus having the appearance of the tube of a perianth. Stamens numerous, inserted at the mouth of the torus. Carpels many, free, included within the. tubular torus, 1- or 2-seeded; seeds erect, exalbuminous. A small group of about four species from North America and Japan. The only two genera referred here are both represented in our gardens.