Page:Scientific results HMS Challenger vol 18 part 1.djvu/289

Rh 8. Thecosphæra entactinia, n. sp.

Cortical shell thick walled, smooth, with regular circular pores of the same breadth as the bars. Radial proportion of the three spheres = 1 : 3 : 12; they are connected by very numerous (forty to fifty, or more) thin radial beams.

Dimensions.—Diameter of the outer shell 0.24, middle 0.06, inner 0.02; cortical pores and bars 0.008.

Habitat.—Central Pacific, Station 268, depth 2900 fathoms.

9. Thecosphæra micropora, n. sp.

Cortical shell thin walled, smooth, with very small and numerous, regular, circular pores, half as broad as the bars. Radial proportion of the three shells = 1 : 2 : 5; they are connected by twenty regularly disposed radial beams.

Dimensions.—Diameter of the outer shell 0.2, middle 0.08, inner 0.04; cortical pores 0.002, bars 0.004.

Habitat.—South Pacific, Station 288, surface.

Definition.—Pores of the cortical shell irregular polygonal, of unequal size or dissimilar form.

10. Thecosphæra capillacea, n. sp.

Cortical shell thin walled, smooth, with irregular polygonal pores, three to six times as broad as the bars. Both medullary shells with similar, but smaller, pores. Radial proportion of the three spheres = 1 : 3 : 8; they are connected by very numerous (sixty to eighty or more) thin radial beams. (Similar to Actinomma capillaceum, Pl. 29, fig. 6, but without external spines.)

Dimensions.—Diameter of the outer shell 0.2, middle 0.075, inner 0.025; cortical pores 0.006 to 0.012, bars 0.002.

Habitat.—North Pacific, Station 250, surface.

11. Thecosphæra diplococcus, n. sp.

Cortical shell thick walled, rough, with large irregular polygonal pores, two to three times as broad as the bars. Both medullary shells with small regular circular pores. Radial proportion of the three spheres = 1 : 2 : 6; they are connected by twenty (?) stout radial beams.

Dimensions.—Diameter of the outer shell 0.12, middle 0.04, inner 0.02; cortical pores 0.008 to 0.012, bars 0.004.

Habitat.—South Atlantic, Station 330, surface.

Definition.—Pores of the cortical shell irregular, roundish, of unequal size or dissimilar form.