1996-97 - Birbal Sahni Institute of Palaeobotany

1996-97
Fine structure of cuticlJiar membrane of Dicroidium sp. from Late Triassic of Tiki Formation, Madhya
Pradesh showing "herring bone" structure indicating environmental strcss,x 62,000.
sedimentological grounds, Late Triassic in India is believed to have been a period of
widespread aridity.
H.K. Maheshwari & S.M. Singh
Investigated about 200 specimens of cordaites and glossopterids. Cuticular
preparations were made from a large number of specimens, but in most specimens the
cellular structure is not decipherable. The preservational aspect, i.e., taphonomy of
this assemblage is very interesting. Some of the leaf megafossils show a peculiar
distortion of the lamina, that may represent effects of depositional environment.
Usha Bajpai & S.M. Singh
Further collected more specimens similar to those earlier reported to
superficially resemble a sphenopsid. The specimens have leaves arranged in a close
spiral on a relatively thick axis. Further maceration of the carbonified crust did not
yield a stomatiferous surface thus handicapping precise comparison of the fossil with
known taxa. The leaves are dimorphic, some are linear-Ianceolate with parallel running
straight veins, while others are cuneate with spreading venation. None of the leaves
show signs of anastomoses.
H.K.
Maheshwari
Analysed the available data on the glossopterid group of plants for taxonomic
position and affinities of the group. This group is mostly known through leaves that
invariably were simple, with smooth margins and reticulate venation. Due to regular
association, pycnoxylic Araucarioxylon-type stems and Vertebra ria roots have been
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