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Keywords from Image Description:
GraptoliteEchinosphaerites. en Encrusting graptolite Thallograptus sphaericola on the cystoid Echinosphaerites aurantium Middle Ordovician northeastern Estonia own Wilson Photograph taken by Mark Wilson Department of Geology The College of Wooster wooster edu html Thallograptus Echinosphaerites Cystoidea fossils Graptolithina