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"The Tubularidae are a family of hydroid polypes are for the most part social animals, frequently possessing a polypidom, which, however, when present, is of much less firm consistence than the horny framework of the Sertularidae. The polypes are never entirely retractable within their tubes; the upper extremity is enlarged into a clavate head, surrounded by a variable number of tentacles." — Goodrich, 1859

Tubularia coronata

"The Tubularidae are a family of hydroid polypes are for the most part social animals, frequently possessing…