Page:Scientific results HMS Challenger vol 18 part 2.djvu/402

1278 as broad as the thorax, with twenty-four to thirty slender, convergent feet, which are as long as the entire shell, with their edges in close contact and their distal ends pointed.

Dimensions.—Cephalis 0.03 long, 0.05 broad; thorax 0.12 long, 0.12 broad.

Habitat.—Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

Definition.—, (vel Dicyrtida multiradiata aperta) without thoracic ribs, with numerous (twelve to fifteen or more) subterminal feet, which are separated from the constricted mouth by a ring of lattice-work. Cephalis free, with an apical horn.

The genus Anthocyrtidium has been derived from the preceding Anthocyrtium by further growth and constriction of the peristome, which becomes separated from the subterminal corona of feet by a more or less broad ring of lattice-work.

1. Anthocyrtidium cineraria, n. sp. (Pl. 62, fig. 16).

Shell campanulate, smooth, with obliterated collar stricture. Length of the two joints = 5 : 11, breadth = 3 : 13. Cephalis subcylindrical-ovate, with a conical straight horn of half the length. Thorax hemispherical, inflated, nearly twice as broad as the constricted mouth. Pores subregular, circular, double-contoured. Above the mouth, separated from it by two rows of pores, a corona of twelve to fifteen short conical feet, which are directed downwards, slightly curved, and as long as the cephalic horn.

Dimensions.—Cephalis 0.05 long, 0.03 broad; thorax 0.11 long, 0.13 broad.

Habitat.—Central Pacific, Station 271, depth 2425 fathoms.

2. Anthocyrtidium ligularia, n. sp. (Pl. 62, fig. 15).

Shell campanulate, rough, with distinct collar stricture. Length of the two joints = 1 : 4, breadth = 2 : 6. Cephalis hemispherical, with a slender, conical, slightly curved horn, about as long as the shell. Thorax hemispherical, three times as broad as the cephalis, nearly twice as broad as the constricted mouth, which is prolonged into a prominent smooth ring. Above the mouth, separated from it by one row of pores, a corona of twelve to fifteen slender linear feet, which are slightly curved, divergent, and emarginate at the truncated distal end.

Dimensions.—Cephalis 0.015 long, 0.03 broad; thorax 0.06 long, 0.09 broad.

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