A small family, distributed from the southern United States to Chili; hairy herbs or low shrubs, without stipules; leaves alternate; two bracts on the flower-stalk; flowers purplish, irregular, perfect; sepals four or five, usually large, the outer one commonly wider than the others; petals usually five, smaller than the sepals, the three upper ones with long claws, often united by their claws, sometimes the middle one of the three lacking, the two lower ones reduced to mere fleshy glands and not resembling petals; stamens three or four, united at least at base; ovary superior, with a slender style; fruit spiny, seed one.