2. Acontaspis hastata, n. sp. (Pl. [134], fig. 16).
Shell thick walled, with numerous (one hundred and seventy to one hundred and ninety) dimples, which are separated by an elevated network of prominent crests. In the centre of each plate a larger dimple with a couple of aspinal pores, surrounded by a corona of ten or twelve smaller dimples, each of which contains a single pore (a coronal and sutural alternately). All pores circular or roundish, nearly of the same size. If the shell be quite regularly developed, there are fifty to sixty sutural pores and one hundred to one hundred and ten coronal pores (six in each equatorial plate, five in each of the other plates). The knobs of the meeting crests are conical, and bear each a simple short by-spine. Radial main spines compressed, at the distal end spear-shaped, with a rhomboidal plate below the apex, about as long as the radius.
Dimensions.—Diameter of the shell 0.18, of the pores and bars 0.01.
Habitat.—Western Tropical Pacific (off the Philippines), Station 215.
3. Acontaspis furcata, n. sp.
Shell thick walled, dimply, with a network of crests, of the same composition as in the foregoing species, with one hundred and seventy to one hundred and ninety dimples (twenty aspinal, one hundred to one hundred and ten coronal and fifty to sixty sutural dimples). All dimples and pores nearly of the same size. Each node of the crested network bears a stout by-spine, which is forked on the base, with two divergent straight branches (similar to those of Hystrichaspis furcata, Pl. [138], fig. 9). Radial main spines two-edged, sword-like, nearly as long as the diameter of the shell.
Dimensions.—Diameter of the shell 0.13, of the pores 0.008.
Habitat.—Central Pacific, Station 272, surface.
4. Acontaspis capillata, n. sp.
Shell very dark and thick walled, non-transparent, with very numerous (three hundred to four hundred or more?) deep funnel-shaped dimples, each of which is perforated by a small circular pore (forty aspinal, two hundred to three hundred coronal, and fifty to one hundred sutural pores?). The high crests between the dimples bear very numerous simple by-spines, nearly half as long as the radius, so that the shell appears covered with hairs. Radial main spines very long and thin, cylindrical, longer than the diameter of the shell.