Dimensions.—Diameter of the outer shell 0.13, inner 0.05, inner and outer pores 0.008 to 0.012, bars 0.004.
Habitat.—Central Pacific, Station 271, depth 2425 fathoms.
Genus 20. Liosphæra,[[32]] Haeckel, 1881, Prodromus, p. 449.
Definition.—Liosphærida with two cortical (extracapsular) shells (without a medullary or intracapsular shell).
The genus Liosphæra agrees with the preceding Carposphæra in the possession of two concentric latticed spheres; but whilst in the latter genus the inner sphere is a medullary one (intracapsular), the outer a cortical shell (extracapsular), both connected by radial beams piercing the capsule-wall, here in Liosphæra the central capsule lies freely within the inner lattice shell and is not pierced by radial beams. Therefore both shells are here cortical shells, both separated by a distance, which is constantly much smaller than the radius of the inner shell; whereas in Carposphæra this distance is at least as large as that radius (commonly much larger). In Carposphæra the number of pores in both shells is never the same; in several species of Liosphæra this number is the same, each outer regular hexagonal pore exactly corresponding to an inner; the six corners of each connected by six short radial beams.
Subgenus 1. Melitomma, Haeckel.
Definition.—Pores of both shells regular, in each shell all of nearly equal size and form.
1. Liosphæra hexagonia, n. sp. (Pl. [20], fig. 3).
Both shells with the same number of pores, exactly corresponding, about ten on the quadrant. All pores regular, or subregular, hexagonal; the outer twice as broad as the inner. Outer bars very thin, thread-like; inner bars thick, one-third as broad as the pores. Surface smooth. Both shells connected by numerous radial beams, their distance one-third as large as the radius of the inner shell.
Dimensions.—Diameter of the outer shell 0.16, inner 0.12, distance of both 0.02; outer pores 0.014, inner pores 0.007.