Flora of North America species comparison

slender to stout, erect to prostrate or decumbent, unbranched to sparsely branched.

cauline, alternate;

stipules absent;

sessile or petiolate, petiole usually shorter than blade;

blade margins entire or denticulate.

usually racemes or spikes, rarely panicles;

buds erect or pendent.

bisexual, usually actinomorphic, often protandrous;

floral tube deciduous (with sepals, petals, and stamens) after anthesis, usually with basal nectary and a ring of hairs inside;

sepals 4, often pink to purplish red, usually connate to tip in bud, reflexed singly, in pairs, or all together to 1 side at anthesis;

petals 4, usually lavender or pink to dark reddish purple, pale yellow or white, [rarely blue (C. tenella)], often spotted, flecked or streaked with red, purple, or white;

stamens 8, in 2 equal or unequal series, or 4 in 1 series, filaments filiform or expanded distally, sometimes subtended by hairy scales, anthers basifixed, often with short acute sterile tip, pollen cream, yellow, blue-gray, lavender, or red, shed singly;

ovary 4-locular, stigma 4-lobed, commissural, lobes receptive only on dry, unicellular-papillose inner surfaces.

a capsule, elongate, straight or curved, cylindrical, fusiform, or subclavate, often 4-angled (shallowly to deeply 4- or 8-grooved) or terete, loculicidal, often tardily dehiscent, sometimes with sterile beak, rarely short, indehiscent and nutlike (C. heterandra);

sessile or pedicellate.

usually numerous, rarely (C. heterandra) 1 or 2, usually angled, cubic, or elongate to spindle-shaped, often with crest of elongated cells, scaly or minutely tuberculate.