Pores irregular, roundish, one to two times as broad as the bars; ten to twelve on the half equator. Surface of the thick-walled shell covered with numerous short conical thorns. Polar spines cylindro-conical, one and a half to two times as long as the axis of the sphere.
Dimensions.—Diameter of the sphere 0.18, pores 0.01 to 0.015, bars 0.008; length of the polar spines 0.25 to 0.3, thickness 0.02.
Habitat.—Indian Ocean, surface; Ceylon, Haeckel.
Genus 46. Xiphostylus,[[69]] Haeckel, 1881, Prodromus, p. 450.
Definition.—Stylosphærida with one single lattice-sphere and two free spines of different size or form.
The genus Xiphostylus differs from the foregoing Xiphosphæra in the unequal size or form of both polar spines, which become more or less differentiated.
Subgenus 1. Xiphostylantha, Haeckel.
Definition.—Pores of the spherical shell regular, of nearly equal size and form; surface smooth or a little rough, without spines or thorns.
1. Xiphostylus alcedo, n. sp. (Pl. [13], fig. 4).
Pores regular, circular, with elevated hexagonal frames, twice as broad as the bars. Eight to ten pores on the half equator. Surface smooth. Polar spines three-sided pyramidal, as broad at the base as one hexagon; the major spine four to five times as long as the minor, which is about equal to the radius of the sphere.