Not a very large family, all but one natives of America; herbs, armed with hooked, stinging or sticky hairs; without stipules; the flowers perfect, with five sepals and five to ten petals; the stamens numerous, with threadlike filaments, the outer ones sometimes petal-like, inserted with the petals on the throat of the calyx and usually arranged in clusters opposite the petals; the ovary inferior, with a threadlike style; the capsule crowned with the calyx-lobes.

There are many kinds of Mentzelia, all western, often with white shining stems and alternate leaves; the calyx cylindrical or top-shaped, with five lobes; the petals five or ten; the styles three, somewhat united. The barbed hairs which clothe the stems and leaves make the plant stick to whatever it touches, probably helping to distribute the seeds, hence the common name Stick-leaf.