1. Palaeobotany and Palynology Laboratory, Department of Botany Sidho‐Kanho‐Birsha University Ranchi Road Purulia 723104 India
2. Centre of Advanced Study, Department of Botany University of Calcutta 35, BC Road Kolkata 700019 India
3. Geological Studies Unit, Indian Statistical Institute 203, B.T. Road Kolkata 700108 West Bengal India