Both proximal chambers kidney-shaped, both distal chambers nearly hemispherical, somewhat smaller. Pores irregular, roundish, twice to three times as broad as the bars; four to six on the half meridian, eight to ten on the half equator of each chamber; a circle of larger square pores on the base of each distal chamber. Surface thorny. On both poles of the main axis one strong, pyramidal, apical spine, one-third as long as the main axis, on the base one-fourth as broad as the equatorial constriction. (Similar to Panarium tubularium, Pl. [40], fig. 9, but without tubes.)
Dimensions.—Main axis (without polar spines) 0.2, equatorial axis 0.05; pores 0.005 to 0.01, bars 0.003; length of the polar spines 0.07, basal thickness 0.012.
Habitat.—Antarctic, Station 156, depth 1975 fathoms.
Subgenus 2. Panartidium, Haeckel.
Definition.—On both poles of the main axis a bunch or a circle of aggregated spines.
3. Panicium scoparium, n. sp.
Both proximal chambers kidney-shaped, both distal chambers nearly hemispherical, somewhat smaller. Pores irregular, polygonal, twice to five times as broad as the bars; six to eight on the half meridian, twelve to fourteen on the half equator of each chamber. Surface spiny, covered with thin, bristle-like spines. On both poles of the main axis a bunch of six to eight aggregated larger conical spines, about as high as a single chamber.
Dimensions.—Main axis (without polar spines) 0.2, equatorial axis 0.06; pores 0.005 to 0.015, bars 0.003; length of the polar spines 0.05, basal thickness 0.005.
Habitat.—Pacific, central area, Stations 270 to 274, depth 2350 to 2925 fathoms.
4. Panicium coronatum, n. sp. (Pl. [40], fig. 4).