Source : Webster's Revised Unabridged Dictionary (1913)

Ceratospongiae \Cer`a*to*spon"gi*[ae]\, n. pl. [NL., fr. Gr.
   ke`ras, ke`ratos horn + ? sponge.] (Zo["o]l.)
   An order of sponges in which the skeleton consists of horny
   fibers. It includes all the commercial sponges.