some sort of embryo of particular hydroids Tubularia having a stellate kind
- some sort of embryo of certain hydroids (Tubularia), having a stellate kind.
(n. pl.) A kind of embryo of specific hydroids (Tubularia), having a stellate form.
The parasitic actinula is found attached to the proboscis of the medusa; it thrusts its greatly elongated hypostome into the mouth of the medusa and nourishes itself upon the food in the digestive cavity of its host.