Page:Scientific results HMS Challenger vol 18 part 1.djvu/362

154 6. Staurosphæra jacobi, n. sp.

Shell thick walled, smooth, with regular, circular pores, twice as broad as the bars; eleven to twelve on the quadrant. Four spines cylindrical, three times as long as the radius, three times as broad as one mesh.

Dimensions.—Diameter of the shell 0.1, pores 0.006, bars 0.003.

Habitat.—North Atlantic, Station 353, depth 2965 fathoms.

7. Staurosphæra simonis, n. sp.

Haliomma with four spines, Bury, 1862, Polycystins of Barbados, pl. iv. fig. 4.

Shell thick walled, smooth, with regular, circular pores, of the same breadth as the bars; eight to ten on the quadrant. Four spines cylindrical, twice as long as the radius, five times as broad as one mesh.

Dimensions.—Diameter of the sphere 0.1, pores and bars 0.003.

Habitat.—Fossil in Barbados.

Definition.—Pores regular, all of nearly equal size and similar form; surface covered with by-spines or accessory thorns.

8. Staurosphæra philippi, n. sp. (Pl. 15, fig. 6).

Shell thin walled, covered with bristle-shaped by-spines, as long as the radius. Pores regular, circular, twice as broad as the bars; six to eight on the quadrant. Four main spines cylindrical, five to ten times as long as the radius, as broad as one mesh.

Dimensions.—Diameter of the shell 0.08, pores 0.006, bars 0.003.

Habitat.—Central Pacific, Station 272, surface.

9. Staurosphæra andreæ, n. sp.

Shell thick walled, with regular, circular, hexagonally framed pores, three times as broad as the bars; nine to ten on the quadrant. From each hexagon-corner arises a bristle-shaped by-spine, half as long as the radius. Four main spines three-sided pyramidal, with spirally contorted edges, as long as the radius (very similar to Hexastylus solonis, Pl. 21, fig. 11, but with only four spines).

Dimensions.—Diameter of the shell 0.16, pores 0.01, bars 0.003.

Habitat.—Central Pacific, Station 265, depth 2900 fathoms.