Subgenus 1. Diplosphærella, Haeckel.
Definition.—Radial main spines simple, without lateral branches.
1. Diplosphæra hexagonalis, n. sp. (Pl. [19], fig. 3).
Inner shell with regular, hexagonal meshes and very thin thread-like bars; at each nodal-point one bristle-shaped by-spine; outer shell twice as broad, with simple triangular meshes. Radial spines with three smooth edges. (The radially striped central capsule, enclosed in the inner shell, envelops a large central nucleus one-third its size, fig. 3.)
Dimensions.—Diameter of the outer shell 0.36, inner 0.18.
Habitat.—Central Pacific, Stations 265 to 274, surface.
2. Diplosphæra ornata, n. sp.
Inner shell with regular, hexagonal meshes, four times as broad as the bars; outer shell three times as broad, with simple triangular meshes. Radial main spines as well as the bars of both shells very elegantly denticulated; radial by-spines (very numerous in the surface of the inner shell) smooth.
Dimensions.—Diameter of the outer shell 0.7, inner 0.24.
Habitat.—Indian Ocean, Madagascar, surface, Rabbe.