Actiniform

[Eng. & Lat. actinia, and Eng. form, or Lat. form a.] Of the form of an Actinia, shaped like an Actinia. "Many of the large actiniform polypes of the tropical seas combine with a structure which is e entially similar to our own sea-anemones, an external calcareous axis or skeleton." Owen : Compar . Anat ., Invertebr. Anim, Lect. VII.