Subgenus 1. Spongasteriscinus, Haeckel.
Definition.—Cross formed by the four arms regular, rectangular, with equal-sized and equidistant arms.
1. Spongasteriscus ovatus, n. sp.
Arms at equal distances, forming a regular, rectangular cross, egg-shaped, with a broader rounded distal end, one and a third times as long as broad, and three times as long as the radius of the central disk; in the latter three to four concentric rings.
Dimensions.—Radius of the arms 0.1, greatest breadth 0.06.
Habitat.—Western Tropical Pacific, Station 225.
2. Spongasteriscus clavatus, n. sp.
Arms at equal distances, forming a regular, rectangular cross, club-shaped, about as long as the diameter of the central disk, and at their rounded distal end one and a third times as long as broad, at their narrow base only one third as broad. In the centre five to six concentric rings.
Dimensions.—Radius of the arms 0.13, distal breadth 0.06, basal breadth 0.02.
Habitat.—Pacific, central area. Station 271, surface.