Spines four-winged, prismatic in the basal and the distal third. Apex pyramidal, short. Base with large leaf-cross. Four apophyses wing-shaped, nearly semicircular, with dentated edges and rough spinulate or porous faces; their base occupies the middle third of the length of each spine.
Dimensions.—Length of the spines 0.2 to 0.3, greatest breadth (diagonal of the apophysial cross) 0.08 to 0.12.
Habitat.—Tropical Atlantic, Stations 342 to 352, surface.
12. Xiphacantha alata, Haeckel.
Xiphacantha alata, Haeckel, 1862, Monogr. d. Radiol., p. 388.
Acanthometra alata, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 48, Taf. ix. figs. 1-3.
Spines four-winged, prismatic in the basal quarter, more slender in the distal half. Apex simple pyramidal. Base with small wing-cross. Four apophyses wing-shaped, nearly semicircular, with denticulated edges (and often also with spinulate faces); their base occupies the second quarter of the length of each spine.
Dimensions.—Length of the spines 0.3 to 0.4, greatest breadth (diagonal of the apophysial cross) 0.05 to 0.06.
Habitat.—Mediterranean (Nice), Müller, (Portofino), Haeckel.