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"These animals are generally called <em>Tree-corals</em>, on account of the forms of the polypidons which they build and in which they live. They are very small, and possess twelve short tentacles placed in a circle around the mouth; they occupy the cells in the polypidom, which is of a porus nature, the openings of the cells being placed at the summits of tubercular prominences of greater or lesser elevations. " &mdash; Goodrich, 1859

Tree-coral

"These animals are generally called Tree-corals, on account of the forms of the polypidons…