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Plate XIII Report on certain Hydroid Alcyonarian and Madreporarian Corals procured during the Voyage of H.M.S ext. Enlarged view of vertical section of the cnostcum Zooidcavity or pore Branches of the canalsystem Structures occurring in Millepora nodosa File Plate XIII Report on certain Hydroid Alcyonarian and Madreporarian Corals