calcispongiae

from The Collaborative International Dictionary of English v.0.48

Calcispongiae \Cal`ci*spon"gi*[ae]\, n. pl. [NL., fr. L. calx,
   calcis, lime + spongia a sponge.] (Zool.)
   An order of marine sponges, containing calcareous spicules.
   See {Porifera}.
   [1913 Webster]