PLANT: Shrubs, ours weakly armed. STEMS several to many, intricately branched, widely spreading; branches alternate or opposite; twigs woolly to glabrous with age.

LEAVES: evergreen or deciduous, alternate or fascicled, petiolate; blades elliptic to oblong or ovate to obovate, pinnately-veined, entire to serrate, sparsely pubescent.

FLOWERS: perfect, pedicellate; hypanthium hemispheric; sepals triangular; petals 5; stamens 5, ovary less than to one third inferior; style 3-lobed.

INFLORESCENCE: axillary clusters.

FRUITS: capsules, 3- loculed; seeds 3, 1 per locule.

NOTES: 31 spp. worldwide (1 in AZ), especially in warm places. (Coluber; an ancient Latin name meaning snake-like).