Cystidea
Cystidea (s?s-t?d"?-?) , noun, plural
[New Latin, from Greek {not transcribed} a bladder, pouch.]
(Zoology) An order of Crinoidea, mostly fossils of the Paleozoic rocks. They were usually roundish or egg-shaped, and often unsymmetrical; some were sessile, others had short stems.