Campanularia. a common genus of Hydroids (q.v.), and type of a family, Campanulariæ. The delicate stem bearing the colony of polyps may be simple or branched; the nutritive individuals are surrounded by transparent bell-shaped sheaths, within which they may be retracted.
The mouthless, tentacle-less, reproductive individuals bud off sexual ones, which do not, however, go free as they so often do in allied genera. The group of generative buds produced by the reproductive person is inclosed within a special sac-shaped sheath, and the whole thing is called a sporosac. In allied genera, though not in Campanularia, the sexual buds go off as 'swimming-bells', and from their generative products and embryos the fixed asexual plant-like 'zoophyte' is again formed. The genus is common in north European seas and in the Mediterranean. Allied genera are Campanularia, Clytia, Hincksia, Lomedea (with sporosacs), and Eucope, and Obelia (with free swimming-bells). See HYDROIDS;
Johnston's British Zoophytes; Allman's Ray Society Monograph on Hydromedusæ.