any one of the order of fossil echinoderms Cystidea
Examples of 'cystid' in a sentence
cystid
Prominent smooth apertural muscles extend from the basal cystid wall to each lateral side of the vestibular wall.
Wanninger Andreas, Wood Timothy S, Schwaha Thomas 2011, 'Myoanatomy and serotonergic nervous system of the ctenostome Hislopia malayensis:evolutionary trends in bodyplan patterning of ectoprocta', Frontiers in Zoologyhttp://www.frontiersinzoology.com/content/8/1/11. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)