Zooecia either arising from a stolon, without lateral connexion with one another, or laterally united to form sheets.
In the first place, buds may be produced only from the hydrorhiza, which grows out and branches to form a basal stolon, typically net-like, spreading over the substratum to which the founderpolyp attached itself.
From the stolon the daughter-polyps grow up vertically.
Budding from the hydrocaulus may be combined with budding from the hydrorhiza, so that numer ous branching colonies arise from a common basal stolon.
Buds may be produced from the manubrium, radial canals, ring-canal, or tentaclebases, or from an aboral stolon (Narcomedusae).