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Keywords from Image Description:
The Quarterly journal of the Geological Society of London . PROM ALGIERS TO THE SAHARA Hemiaster or Penaster resembling Penaster Fournelli from the Hip purite limestone Brissus Avicula Inoceramus Lucina Cardium Area Byssoarca Cardita Cyrena Cwullcea Clavatula These stand out as bosses from the matrix with weathered black surface