Haeckel, 1879
Medusae typically bell-shaped. Gonads confined to manubrium, sometimes extending to most proximal parts of radial canal. Marginal sense organs, if present, are ocelli, never statocysts or cordyli. Marginal tentacles peripheral, hollow or solid. Hydroids athecate, body not covered by rigid perisarc. Cnidome normally with desmonemes.
Order Filifera
Order Capitata