circoporidæ

Century Dictionary and Cyclopedia

1. A family of tripyleans with a fenestrated shell which is spherical, subspherical, or polyhedric in shape. Sometimes the shell is composed of reticulated plates; it always has one large principal opening and several detached porous areas, and usually hollow radial spicules. Leading genera are Circoporus, Porostephanus, and Porospathis.