Calyx made up of 5, polysepalous, petaloid, posterior one modified into spur.
Corolla consists of 4 petals with fifth one reduced, gamopetalous, 2 posterior petals form the spur which enters the spur of sepal, blue, pink, lavender or white coloured.
Stamens 15 in 5 groups of 3 each, polyandrous, filaments flattened, dithecous, adnate, extrorse.
Carpel one, ovary superior, unilocular with many ovules, stigma simple.