[L. corallum CORAL; applied in a special sense.] A coral; the calcareous skeleton of a coral polypidom; also the horny, suberose, or siliceous tubular envelope of any zoophyte, whether colonial or simple.
1846. Dana, Zooph., ii. § 9 (1848), 15. The corallum in the live Zoophyte is … in general wholly concealed within the polyps.
1855. Gosse, Marine Zool., I. 18. Hydroida … animals either naked, or inclosed in a horny, tubular envelope (corallum). Ibid., 24. Antennularia. Corallum simple or branched, jointed, with slender hair-like branchlets set in whorls.
1878. Huxley, Physiogr., xv. 251. The skeleton, or corallum … is left as a contribution to the solid floor of the sea.
