Page:Scientific results HMS Challenger vol 18 part 2.djvu/188

1064 16. Petalospyris furcata, n. sp.

Shell nut-shaped, smooth, with sharp sagittal stricture. Pores numerous, small, and circular; no larger annular pores. Basal plate with four larger and four alternate pairs of smaller pores. Horn conical, about as long as the shell. Feet fifteen to twenty, broadly lamellar, about twice as long as the shell, in the distal half forked.

Dimensions.—Shell 0.04 long, 0.06 broad; horn 0.05 long, feet 0.1 long.

Habitat.—South Pacific, Station 300, depth 1375 fathoms.

17. Petalospyris lobata, n. sp. (Pl. 87, fig. 13).

Shell subspherical, smooth, with slight sagittal stricture. Pores small, roundish; on each side of the ring two pairs of larger annular pores. Basal plate with four pores. Horn stout, three-sided prismatic, half as long as the shell. Feet twelve to sixteen, lamellar, lobate (the most part with three lobes), nearly vertical, about as long as the shell.

Dimensions.—Shell diameter 0.05; horn 0.03, feet 0.05 long.

Habitat.—South Atlantic, Station 335, depth 1425 fathoms.

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

The genus Anthospyris differs from the preceding Petalospyris, its ancestral form, in the possession of three horns on the coryphal face (one odd middle apical horn and two paired frontal horns, one on each side). The former therefore bears to the latter the same relation that Triceraspyris does to Tripospyris and Liriospyris to Hexaspyris.

1. Anthospyris mammillata, n. sp. (Pl. 87, fig. 16).

Shell nut-shaped, mammillate, with deep sagittal stricture and irregular, polygonal pores. Basal plate with two large ovate pores (?). The pediculate apical horn and the two frontal horns stout and short, conical, twice to three times as large as the conical papillæ of the surface. Feet twelve to fifteen, lanceolate lamellar, pointed, divergent, about as long as the shell.

Dimensions.—Shell 0.05 long, 0.08 broad; horns 0.03, feet 0.04 long.

Habitat.—Central Pacific, Station 272, depth 2600 fathoms.