Dimensions.—Length of the spines 0.2, breadth 0.02.
Habitat.—Central Pacific, Station 271, surface.
Genus 329. Astrolonche,[[369]] Haeckel, 1881, Prodromus, p. 465.
Definition.—Astrolonchida with numerous simple apophyses (four to eight or more on each radial spine), which are arranged in two opposite longitudinal rows (rarely in six such rows, opposite in three parallel planes).
The genus Astrolonche differs from the preceding Phractacanthida in the multiplication of the simple apophyses. Commonly these are opposite in pairs in two longitudinal rows (on the two edges of the compressed spine, at least two on each side). But sometimes (in the subgenus Astrolonchidium) there are six instead of two longitudinal rows of teeth, and these are placed in three parallel planes.
Subgenus 1. Astroloncharium, Haeckel.
Definition.—Each spine with two longitudinal rows of apophyses, opposite in one meridian plane.
1. Astrolonche bicruciata, n. sp.
Spines compressed, two-edged, almost of equal breadth throughout their whole length, with simple apex and small leaf-cross at the base. From the two edges of the middle part of each spine arise two pairs of opposite apophyses, which are compressed and a little curved (convex on the distal, concave on the proximal margin). All four apophyses are of the same size and form; the radial distance of each pair much smaller than their common distance from the centre.
Dimensions.—Length of the spines 0.25, breadth 0.02.