In this article we will discuss about the structure of plumularia with the help of diagrams.
1. It is a marine, colonial, luminescent form.
2. The colony is feather-like and are attached to highly branched hydrorhizae.
3. The branches (hydrocladium) come out from the main stem alternately and bear sessile hydro theca only on upper surface.
4. The polyp bears a small hypostome surrounded by a ring of tentacles.
5. Blastostyles or gonagia are unprotected and without gonotheca.
6. In addition to normal polyps there are also present special polyps the nematophores which are devoid of tentacles and mouth but have long amoeboid projections. These are defensive polyps.