Definition.—Spongy cortical shell immediately enclosing the lentelliptical medullary shell, without hollow interval.
1. Spongophortis spongiosa, n. sp.
Cortical shell irregular, roundish, rough or tuberous, composed of loose spongy framework, which immediately envelops the lentelliptical central Larnacilla-shell; the diameter of the former becomes about five to six times as large as that of the latter.
Dimensions.—Diameter of the spongy cortical shell 0.15 to 0.25, of the trizonal medullary shell 0.03 to 0.04.
Habitat.—Pacific, central area, Station 274, surface.
Subgenus 2. Spongophorticium, Haeckel.
Definition.—Spongy cortical shell separated by a hollow interval from the lentelliptical medullary shell.
2. Spongophortis radiosa, n. sp.
Cortical shell irregular, roundish, four to five times as large as the enclosed lentelliptical Larnacilla-shell, with which it is connected by ten to twenty irregularly disposed radial beams. Spongy framework compact, about as thick as the medullary shell. Surface covered with numerous short, bristle-shaped, radial spines.
Dimensions.—Diameter of the spongy cortical shell 0.15 to 0.2, of the trizonal medullary shell 0.035 to 0.045.