Page:Scientific results HMS Challenger vol 18 part 1.djvu/435

Rh tree, with straight, stout, three-sided pyramidal stem. From the dentated edges arise numerous verticillate branches, the proximal ends of which are thickly ramified. (Differs from the preceding and similar species mainly in the large size and irregular lattice-work of the shell.)

Dimensions.—Diameter of the shell 0.12 to 0.14, pores 0.006 to 0.012, bars 0.003; length of the spines 0.25 to 0.4, breadth 0.012.

Habitat.—North Pacific, Station 256, surface.

12. Cladococcus tricladus, n. sp.

Pores irregular, polygonal, twice to eight times as broad as the bars; eight to ten on the radius. About twenty radial spines, three-sided prismatic, twice as long as the shell diameter; in the proximal half simple, with smooth edges; in the distal half with three diverging curved branches, which bifurcate two to three times or ramify irregularly. (Closely related to the simpler Cladococcus quadricuspis.)

Dimensions.—Diameter of the shell 0.16, pores 0.04 to 0.016, bars 0.002; length of the spines 0.3, breadth 0.012.

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

13. Cladococcus stalactites, n. sp. (Pl. 27, fig. 4).

Pores irregular, roundish, once to five times as broad as the bars; eight to ten on the radius. About twenty radial spines, very stout, longer than the shell diameter, with three wing-like, prominent smooth edges. At the middle, or in the distal half, each spine bears a verticil of three strong, irregularly formed ramified branches.

Dimensions.—Diameter of the shell 0.14, pores 0.003 to 0.015, bars 0.003; length of the spines 0.16 to 0.2, breadth 0.02.

Habitat.—West Tropical Pacific, Station 220, depth 1100 fathoms.

14. Cladococcus dendrites, n. sp. (Pl. 27, fig. 5).

Pores irregular, roundish, with denticulate margin, twice to four times as broad as the bars; eight to twelve on the radius. Fifty to eighty radial spines, three-sided prismatic, with elegantly denticulated edges; in the proximal two-thirds simple, in the distal third with a bunch of ten to twenty short simple spines (three to seven on each edge).

Dimensions.—Diameter of the shell 0.16 to 0.2, pores 0.006 to 0.012, bars 0.003; length of the spines 0.2 to 0.3, breadth 0.01.

Habitat.—Antarctic Ocean, Station 157, depth 1950 fathoms.

Definition.— with one simple lattice-sphere, covered with forked or dichotomously branched radial spines (the stem of the spine always forked).