Ten radial spines, four-sided pyramidal, with prominent smooth edges, gradually thickened from the small pyramidal base towards the truncated distal end.
Dimensions.—Length of the spines 0.3 to 0.4, breadth in the basal part 0.002, in the middle part 0.006, in the distal part 0.012 to 0.02.
Habitat.—Central Pacific, Station 266, surface.
3. Litholophus decapristis, n. sp. (Pl. [129], fig. 2).
Ten radial spines, four-sided prismatic, with prominent, elegantly denticulated edges, of equal breadth in their whole length.
Dimensions.—Length of the spines 0.2 to 0.4, breadth 0.008.
Habitat.—Cosmopolitan; Mediterranean, Atlantic, Pacific, surface.
4. Litholophus decastylus, n. sp.
Ten radial spines, four-winged pyramidal, with broad and thin, elegantly denticulated edges, gradually thickened from the small pyramidal base towards the truncated distal end.
Dimensions.—Length of the spines 0.2 to 0.3, breadth in the basal part 0.002, in the middle part 0.005, in the distal part 0.015.