PLATE 6

A, B, C, D. Successive stages of floral development. Explanation in text: A, x7s; B, x65; C, X60; D, X42; (se) sepal, (ps) procambial strands, (p) petal, (st) sepal procambial trace, (AC) air canal, (qm) quiescent promeristem, (s) stamens, (fa) floral apex, (vp) vascular plexus.