Densely tufted glabrous low evergreen shrubs, with thick rather fleshy imbricated narrow leaves, and solitary terminal erect peduncled white or pink flowers. Calyx 2-4-bracted at the base, the sepals oval, obtuse, somewhat rigid. Corolla campanulate, tardily deciduous, 5-lobed, the lobes obtuse. Stamens 5, inserted at the sinuses of the corolla; filaments short and broad; anther-cells pointed, divergent, obliquely 2-valved; staminodia none. Style slender; ovules numerous in the cells, anatropous. Seeds oblong-cubic, the testa close, reticulated. [Greek, by fives, alluding to the stamens and corolla-lobes.]

Two species, the following typical one of wide distribution in the colder parts of the northern hemisphere, the other Himalayan.

1 Diap nsia L Sp Pl 141 1753 1620

1. Diapensia Lappónica L. Diapensia

Fig. 3278

Diapensia lapponica L. Sp. Pl. 141. 1753.

Glabrous, forming dense cushion-like tufts; stems simple or branched, erect or ascending, 1'-3' high. Leaves crowded below, thick, spatulate, sessile, obtuse or acutish, often curved, entire, 3"-6" long, about 1" wide, the margins usually revolute; peduncles rather stout, becoming 1'-2' long in fruit; sepals and' bracts oval; corolla usually white, 3"-4" long, its tube about the length of the sepals and of its oval or oblong obtuse lobes; capsule ovoid, 2"-3" high.

Summits of the Adirondack Mountains, and of the mountains of New England; Mt. Albert, Quebec; Labrador and arctic America. Also in northern and alpine Europe and Asia. June-July.