Habitat.—Central Pacific, Station 263, depth 2650 fathoms.
8. Sethopyramis hexagonalis, n. sp.
Shell papillate, slender, pyramidal. Cephalis small, hemispherical, with a straight conical horn twice the length, and small circular pores. Thorax conical, with slightly convex outlines and nine stout, somewhat curved ribs in zig-zag form, which are connected by ten to twelve interrupted transverse bars. From each nodal point a small conical papilla arises. The large meshes so produced are regular, hexagonal, gradually increasing in size towards the mouth.
Dimensions.—Cephalis 0.03 diameter; thorax (with twelve transverse rows of meshes) 0.18 long, 0.12 broad.
Habitat.—South Atlantic, Station 335, depth 1425 fathoms.
9. Sethopyramis cyclomma, n. sp.
Shell thorny, slender, pyramidal. Cephalis large, subspherical, with numerous very small circular pores, and a small conical horn of the same length. Thorax similar in form and structure to that of the preceding species; but each hexagonal mesh is provided with a very thin circular hyaline ring (like a diaphragm), so that the openings are not hexagonal, but circular. From each nodal point a short pointed conical or slightly forked spine arises.
Dimensions.—Cephalis 0.02 diameter; thorax (with ten transverse rows of meshes) 0.18 long, 0.14 broad.
Habitat.—Tropical Atlantic, Station 348, depth 2450 fathoms.