The Collaborative International Dictionary of English v.0.48:

Fibrospongiae \Fi`bro*spon"gi*[ae]\, prop. n. pl. [NL., fr. L.
   fibra a fiber + spongia a sponge.] (Zool.)
   An order of sponges having a fibrous skeleton, including the
   commercial sponges.
   [1913 Webster]