Studies in the Glossopteris flora of India - 11. Some observations on Vertebraria from the Lower Gondwana of India

Abstract

Recently a large collection of Vertebrarias was made from Barakar and Raniganj Stages of the Lower Gondwanas. The specimens were studied for anatomical structures bv the "Dry Pull" method. One specimen from the Raniganj Stage shows anatomy different from that of V. indica and hence has been referred to a. new species V. raniganjensis. The collection also includes an axis cast with a small middle part not belonging to the xylem and which looks like a pith. As pith is not known in other species of Vertebraria, it has been given a new specific name V. myelonis. A specimen doubtfully referred to Ctenis by Srivastava (1954) has been found on reinvestigation to be a new species of Glossopteris -G. srivastavai. The anatomy of the midrib of G. srivastavai and V. raniganjensis is almost similar. It is probable that G. srivastavai was one of the leaves borne on an axis of V. raniganjensis.

On the species of genus Glossopteris from barakar formation of Karanpura and Bokaro coalfields, India

“…However, in G. lorluosa the meshes near the midrib are much broader than those near the margin while in G. relifera meshes are of almost equal size throughout the lamina. Surange and Maheshwari (1962;text-fig. 9) figured a whorled cluster of G. 10rlUOsa leaves surrounding an axis of Verlebraria.…”

Seeds, fructifications, bracts and calamitalean axes from the Karanpura and Bokaro Group of coalfields

“…Remarks-Vertebraria indica was established on the basis of external characters of the axes. Surange and Maheshwari (1962) established two more species, viz., V.…”

Taxonomy and diversity of the genus Glossopteris

“…Besides Pant and coworkers, H0eg and Bose (1960). Surange and Maheshwari (1962). Saksena (1963), Rigby (1966).…”

“…Plumstead (1958, p. 92) opined that "it is probable that they were deciduous, woody plants with an arborescent habit, and that the leaves, flowers and fruits were borne on short shoots, a few of which developed into long shoots to form branches". Earlier it was suggested that the genus Vertebraria is one of the stems which bore such leaves (Dolianiti, 1954;Surange & Maheshwari, 1962;Pant. 1962).…”