Cuticular studies of the reproductive organs of Glossopteris Part II - Cistella type Fructification Plumsteadiostrobus ellipticus gen. et sp. nov. attached on Glossopteris Taentoides feistmantel

Abstract

A Cistella type female fructification is described under a new generic 1 ame, Plumsteadiostrobus. It is attached on Glossopteris taenioides Feist. The leaf has similar cuticular characters as described by Srivastava for G. taenioides and by Pant and Nautiyal for an identical leaf but described under a new specific name. We prefer to retain Feistmantel's specific name: The female reproductive organ consists of a receptacle bearing a large number of small seeds arranged in close spiral all round it. The seed bearing receptacle is borne in the axil of a protective bract which closely covers the receptacle like a spathe. The bract and the receptacle is borne on a short common pedicel which is attached to the midrib of Glossopteris taenioides at a distance from the base of the leaf. The reproductive organ is thus adnate to the leaf, which means that the fructification is borne in the axil of the vegetative leaf. The female reproductive organ yields three types of cuticles, two belong to the protective bract and the third belongs to the receptacle. The receptacle cuticle possesses lens shaped openings on which ovules sit. The ovule must be drawing through this hole in the cuticle its vascular supply from the receptacle. The seeds are small, winged, orthotropous, platyspermic and were described by Pant and Nautiyal as Pterygospermum raniganjense in dispersed condition. The cells of the integument contain characteristic crystalline imprints. The nucellus is thickly cutinized and show excavated pollen chamber. Two winged pollen grains are very often found trapped in the pollen chamber. This Cistella type of fructification is distinct from Dictyopteridium and Scutum. One species, Plumsteadiostrobus ellipticus, is described here from the Raniganj Stage of the Raniganj Coalfield, India.