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Keywords from Image Description:
Tetragraptus quadribrachiatus J. Hall. en Tetragraptus quadribrachiatus Reuben Ross William Berry google ph id WktjAAAAIAAJ dq NicholsonTetragraptus source gbsnavlinkss Ordovician Graptolites of the Basin Ranges in California Nevada Utah and Idaho Geological Survey Bulletin Reuben Ross William Berry PDUSGovUSGS PDUSGov