Page:Scientific results HMS Challenger vol 18 part 2.djvu/190

1066 pores and a corona of numerous small peripheral pores. Three horns spindle-shaped, divergent, about half as long as the shell. Feet twenty-five to thirty, broad, lamellar, lanceolate, pointed, divergent, nearly as long as the shell.

Dimensions.—Shell 0.1 long, 0.13 broad; horns 0.06, feet 0.09 long.

Habitat.—South Pacific, Station 296, depth 1825 fathoms.

7. Anthospyris tragopogon, n. sp. (Pl. 87, fig. 17).

Shell nut-shaped, tuberculate, with distinct sagittal stricture and small regular circular pores. Basal plate with numerous small pores. Apical horn very large, spindle-shaped, twice as long as the shell; frontal horns small, scarcely one-fourth as long, curved laterally. Feet twenty-five to thirty, three to four times as long as the shell, lamellar, lanceolate, pointed, parallel, vertical.

Dimensions.—Shell 0.08 long, 0.11 broad; apical horn 0.16, feet 0.2 long.

Habitat.—Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

Definition.— with numerous (seven to twelve or more) basal feet and numerous coryphal horns.

The genus Ceratospyris differs from all the other Zygospyrida in the possession of numerous large spines on the surface of the shell, which usually exhibits only a small number of large pores or meshes. The lower spines which cover the inferior or basal face of the shell (usually nine to twelve or more) may be compared to the descending "basal feet" of the other Zygospyrida; the upper spines, however, which cover the superior or coryphal face (usually six to nine, rarely more), may be regarded as "coryphal horns." In many species of this genus the lattice-work of the shell is of a peculiar loose kind, with few large meshes, resembling the wicker-work of the Plectanida.

Definition.—Spines simple, not branched. Meshes of the shell usually polygonal, or roundish with polygonal frames. Bars of the network prismatic.

1. Ceratospyris polygona, n. sp. (Pl. 86, fig. 1).

Shell polyhedral, with deep sagittal stricture, studded with twenty-four to thirty long simple straight slender pyramidal spines, which are as long as the shell or longer. All pores large, polygonal. On the frontal and the occipital face two pairs of very large pores only, the superior