Deciduous trees with gray bark and small pieces falling off longitudinally; Branchlets have septate pith. The winter bud is oval, surrounded by two attached stipules, and the young leaves are folded in half in the bud and bent downward. Leaves alternate, long-stalked, stipules free petiole, leaf blade apex truncated or slightly concave, with 1 pair or 2 rows of lateral cracks near the base. Flowers are tasteless, single branches and leaves open at the same time, bisexual, perianth segments 9- 17, 3 1, almost equal, anther chamber dehiscence outward; Gynoecium is sessile, carpels are numerous, spirally arranged and separated, the lowest part is sterile, and 2 ovules per carpel hang from the top of ovary. Aggregate fruit is spindle-shaped, mature carpels are woody, the seed coat and endocarp are healed, the top extends into a wing shape, and it falls off from the receptacle when it matures, and the receptacle persists; 1-2 seed with thin and dry seed coat and embryo hidden in endosperm. The wall of the wooden catheter is not thickened by threads, and the holes between the pipes are aligned; The outer wall of pollen has a thick and prominent carved covering layer, and the outer wall is 2, lacking or thin.

Fossils of Mesozoic and Cretaceous have been found in Japan, Greenland, Italy and France. There are more than 10 species in Cenozoic and Tertiary, which are widely distributed in temperate regions of the northern hemisphere, and most of them died out during the Quaternary Ice Age.

Two kinds. There are 1 species in China and 1 species in North America.

Type species: Tulips in North America.