Habitat.—South Atlantic (east of Buenos Ayres), Station 325, depth 2650 fathoms.
2. Circospathis novena, n. sp. (Pl. [117], figs. 3, 3a).
Shell polyhedral (tetradecahedral), with fourteen triangular, plane, or slightly convex faces, covered with small, irregular, polygonal (usually hexagonal) plates, and nine prominent corners, from which arise nine radial spines, shorter than the diameter of the shell. Each spine is surrounded at the broader base by a circle of twelve to sixteen pores and a corona of bristles, and bears at the inflated distal apex a trident or fuscina, similar to that of Circoporus sexfuscinus (Pl. [115], fig. 2). Mouth with nine convergent, conical, denticulate teeth (fig. 3a).
Dimensions.—Diameter of the shell 0.6, length of the spines 0.4.
Habitat.—South Atlantic, Station 318 (east of Patagonia), depth 2040 fathoms.
3. Circospathis tetradeca, n. sp.
Shell spherical, covered with irregular, polygonal plates. Nine radial spines, cylindrical, as long as the radius of the shell, bristly, armed at the distal apex with a trident. (In one specimen six spines possessed three terminal branches, two spines two branches, and one spine four branches.) The broader base of each spine is surrounded by a corona of nine pores and a circle of curved bristles. Mouth with nine smooth conical teeth.
Dimensions.—Diameter of the shell 0.55, length of the spines 0.3.
Habitat.—South Atlantic, Station 332 (west of Tristan da Cunha), depth 2200 fathoms.
4. Circospathis tetrodonta, n. sp. (Pl. [115], fig. 10).