Dimensions.—Shell diameter 0.07 to 0.08, length of the horn 0.04, of the feet 0.08.
Habitat.—Central Pacific, Station 268, depth 2900 fathoms.
3. Peridium curvipes, n. sp.
Shell hemispherical, thorny, with irregular roundish pores. Basal plate with six pores (two larger middle cardinal, two smaller anterior jugular and two smaller posterior cervical pores, as in Pl. [53], figs. 13, 18). Horn conical, oblique, arising from the middle of the occipital face, half as long as the shell. Feet slender, conical, curved, smooth, twice as long as the shell.
Dimensions.—Shell 0.04 long, 0.06 broad; horn 0.02 long; feet 0.08 long.
Habitat.—Tropical Pacific, Station 206, depth 2100 fathoms.
Subgenus 2. Archiperidium, Haeckel.
Definition.—Feet spiny or branched.
4. Peridium spinipes, n. sp. (Pl. [53], fig. 9).
Shell ovate, rough or thorny, with irregular roundish pores. Basal plate with four pores (two larger cardinal and two smaller jugular pores). Horn oblique, occipital, three-sided pyramidal, half as long as the shell, connected with the caudal foot by a prominent crest. Three feet horizontally expanded, prismatic, spiny, about as long as the shell.