Habitat.—Central Pacific, Station 272, depth 2600 fathoms.
2. Tetraspyris cubica, n. sp.
Shell nearly cubical, smooth, with slight sagittal stricture and small polygonal pores; some larger pores on both sides of the ring. Basal plate with four large collar pores. Apical horn and the four feet of equal size and form, about as long as the shell, cylindrical in the basal, spindle shaped in the distal half.
Dimensions.—Shell 0.09 diameter; horn and feet 0.1 long.
Habitat.—Central Pacific, Station 265, depth 2900 fathoms; also fossil in Barbados.
Subgenus 2. Tetracorethra, Haeckel, 1831, Prodromus, p. 429.
Definition.—Feet branched or forked.
3. Tetraspyris tetracorethra, n. sp. (Pl. [53], figs. 19, 20).
Tetracorethra mirabilis, Haeckel, 1881, Prodromus, p. 439, and Atlas, loc. cit.
Shell campanulate, tuberculate, with deep sagittal stricture and irregular polygonal pores; two pairs of larger pores at the flattened occipital face (fig. 20). Basal plate with four large collar pores. Apical horn very long, thirty to forty times as long as the shell, slender three-sided prismatic, straight, at the distal end irregularly branched, besom-shaped. Four basal feet half as thick as the horn, eight to twelve times as long as the shell, bristle-shaped, irregularly curved and branched, divergent, at the distal end besom-shaped. Central capsule very large; the enclosed small campanulate part sends out through the four collar pores four very long club-shaped basal lobes, half as long as the feet; each lobe contains a large oil-globule (fig. 19).