Morphology of Tinospora cordifolia, with some observations on the origin of the single integument, nature of synergidae, and affinities of the menispermaceae

Abstract

The gynoecium of Tinospora cordifolia consists of 3-6 spirally arranged carpels. When the number is more than three, the last carpel is frequently abortive. Two ovules differentiate at first in each carpel, but later the lower is suppressed. The functional ovule is amphitropous, has only one integument, and is closely pressed inside the carpel. The nucellus shows an epidermal cap. The development of the embryo-sac is quite normal. The synergidae frequently show egg-like structure. The nuclei of the antipodals show a tendency toward division. The single integument appears to have resulted from the fusion of two in the chalazal and suppression of the inner in the micropylar part. The synergidae are of the same nature as the egg. The family Menispermaceae is more closely related to the Ranunculaceae than to the Magnoliaceae.