Habitat.—Pacific, central area, surface; Stations 271 to 274, depths 2425 to 2750 fathoms.
2. Xiphosphæra gæa, n. sp. (Pl. [14], fig. 5).
Pores regular, circular, with prominent hexagonal crests between them. On the half equator ten to twelve pores, of the same breadth as the crested bars. Shell thin walled; surface smooth. Polar spines three-sided prismatic, about twice as long as the axis of the sphere, twice as broad at the base as one pore.
Dimensions.—Diameter of the sphere 0.07 to 0.09, pores and bars 0.005; length of the polar spines 0.15 to 0.2, basal thickness 0.01.
Habitat.—Pacific, central area, Station 274, depth 2750 fathoms.
3. Xiphosphæra venus, n. sp. (Pl. [14], fig. 2).
Pores regular, circular, with prominent hexagonal frames. On the half equator fifteen to eighteen pores, of the same breadth as the bars. Shell very thick walled; surface smooth, honeycomb-like. Polar spines conical, smooth, about as long as the axis of the shell, twice as broad at the base as one pore.
Dimensions.—Diameter of the sphere 0.12 to 0.13, pores and bars 0.005; thickness of the shell wall 0.013; length of the polar spines 0.12 to 0.15, basal breadth 0.01.
Habitat.—Pacific, central area, Station 272, depth 2600 fathoms.
4. Xiphosphæra luna, n. sp.