In this way are formed the familiar feathery colonies of Plumularia, in which the pinnules are all in one plane, while in the allied Antennularia the pinnules are arranged in whorls round the main biserial stem.
- Diagram of sympodial budding, system, from which simple unbranched Plumularia-type.
One class g g of polyps, the dactylozoids of branching in the Plumularia-type; (dz), lose their mouth and compare with fig.
D, Type of Plumularia, Agalma, t, Tentacles.
Spencer, " A new Family of Hydroidea (Clathrozoon), together with a description of the Structure of a new Species of Plumularia," Trans.
Some of the branching forms have a distinct outward resemblance to the polyparies of Sertularia and Plumularia among the recent Hydroida (Calyptoblastea); in none of the unbranching forms, however, is the similarity by any means close.