1. Orosphæra hastigera, n. sp.
Radial spines cylindrical, straight, smooth, simple, about as long as the diameter of the spherical shell, and as broad as its smooth bars. Meshes of the network irregularly polygonal, the majority quadrangular, of different sizes.
Dimensions.—Diameter of the sphere 1.0 to 1.2, length of the radial spines 1.1 to 1.5, middle breadth 0.004.
Habitat.—Central Pacific, Station 272, depth 2600 fathoms.
2. Orosphæra spinigera, n. sp.
Radial spines cylindrical, irregularly curved, thorny, simple, two to three times as long as the diameter of the spherical shell, and as broad as its spiny bars. Meshes of the network irregularly polygonal, the majority pentagonal.
Dimensions.—Diameter of the sphere 1.5 to 1.8, length of the spines 3.0 to 5.0, breadth 0.006.
Habitat.—North Atlantic, Station 353, depth 2965 fathoms.
3. Orosphæra fusigera, n. sp.
Radial spines slender, spindle-shaped, straight, smooth, about as long as the diameter of the spherical or slightly ellipsoidal shell, in the thicker middle part five times as broad as the bars, and tapering equally towards both ends. Meshes of the network irregularly polygonal, the majority quadrangular, separated by smooth bars.
Dimensions.—Diameter of the shell 1.0 to 1.2, length of the spines 1.2 to 1.6, basal breadth 0.02, middle breadth 0.1.
Habitat.—North Pacific, Station 253, depth 3125 fathoms.
4. Orosphæra foveolata, n. sp.
Radial spines spindle-shaped, straight, dimpled, half as long as the radius of the spherical shell and three to five times as thick as the bars. Meshes irregular, polygonal, of very different shapes, separated by dimpled bars. (Similar to Oroscena gegenbauri, Pl. 106, fig. 4, but with spherical dimpled shell, without pyramidal elevations.)
Dimensions.—Diameter of the shell 2.0 to 2.4, length of the spines 0.5, breadth 0.15.
Habitat.—Central Pacific, Station 267, depth 2700 fathoms.
5. Orosphæra serpentina, n. sp. (Pl. 106, fig. 1).
Radial spines cylindrical, dimpled, undulate or curved in a snake-like manner, about as long as the diameter of the ellipsoidal or spherical shell and four to six times as broad as its smooth bars. Meshes very irregular, polygonal.
Dimensions.—Diameter of the shell 1.0 to 1.2, length of the spines 0.12 to 0.15, breadth 0.12.
Habitat.—South Pacific, Station 289, depth 2550 fathoms.
