|any of various sessile echinoderms, esp of the genus Ptilocrinus, in which the body consists of a long stalk attached to a hard surface and bearing a central disc with delicate radiating arms: class Crinoidea (crinoids)|
any crinoid marine invertebrate (phylum Echinodermata) in which the adult is fixed to the sea bottom by a stalk. The stalk is surmounted by a bulbous body with frondlike tentacles; i.e., the animal resembles a plant. The stem consists of limy disks, and the body has an internal skeleton of close-fitting limy plates.
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