In many bilaterian animals members of the Otx gene family are expressed in head or brain structures. Cnidarians, however, have no clearly homologous head and no distinct brain; but an Otx homolog from the jellyfish Podocoryne carnea is highly conserved

The various phases of homo- and heteroclonal encounters between stolons of Podocoryne carnea M. Sars have been studied with the light and electron microscope. The first clone-unspecific actions and reactions to an imminent encounter between the outgrowing

Culture methods are described for Podocoryne carnea, a colonial marine hydroid that is here demonstrated to respond to excess CO2 in the same way as does Hydra. Preliminary experiments suggest that Podocoryne will metabolize test substances added to its

The muscular anatomy of the athecate hydroid Podocoryna carnea hydrorhiza is elucidated. The polyp-stolon junction is characterized by an opening, here called the chloe, in the otherwise continuous hydrorhizal perisarc. The chloe is elliptical when the