The Collaborative International Dictionary of English v.0.48:
Porcelaneous \Por`ce*la"ne*ous\, Porcellaneous \Por`cel*la"ne*ous\, a. 1. Of or pertaining to porcelain; resembling porcelain; as, porcelaneous shells. [1913 Webster] 2. (Zool.) Having a smooth, compact shell without pores; -- said of certain Foraminifera. [1913 Webster]