FL31 actinomorphic regular Flowers whose longitudinal image shows little or no variation irrespective of the angle of the section in relation to the perianth parts.

FL32 slightly zygomorphic bilateral Flowers whose longitudinal image varies slightly according to the angle of the section in relation to the perianth parts. See image under FL33.

FL33 markedly zygomorphic bilateral Flowers whose longitudinal image varies substantially according to the angle of the section in relation to the perianth parts.