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School of Plant Morphology, Meerut College and Department of Botany, Meerut University, Meerut-250005, India.

ABSTRACT

The premordia of the floral appendages are formed in acropetal sequence; however, there is an overlapping in the formation of petal and stamen primordial. The floral apex has a two-layered tunica in all stages of development.  All floral appendages (bracts, sepals, petals, stamens and carpels) are initiated by periclinal divisions in the second tunica layer of the corpus may also contribute to the formation of stamen and carpel primordial.  All appendages are characterized by apical meristem at least for a time and exhibit marginal initiating cells.  The short clay x tube is formed by ontogenetic fusion of the bases of sepals, but the upper part of the corolla tube arises by ontogenetic union of originally free parts and the lower part by zonal or intercalary growth.  The morphological nature of the placenta has been discussed and the present  ontogenetic study suggests that it is an axial structure which morphologically represents the summit of the floral apex.