Dimensions.—Diameter of the sphere 1.0 to 2.0, length of the bars 0.1 to 0.2, breadth 0.001 to 0.002.
Habitat.—Cosmopolitan; Atlantic, Pacific, surface.
Genus 678. Sagenoscena,[[297]] n. gen.
Definition.—Sagosphærida with a delicate spherical shell, the thin wall of which is composed of a simple lattice-plate and covered with numerous pyramidal elevations; each pyramid bears on its top one or more radial spines, and has an internal axial rod in its radial axis.
The genus Sagenoscena differs from the preceding closely allied Sagoscena in the possession of an internal radial axial rod, which arises in the centre of the base of each pyramid, and is prolonged usually over its apex into a free, radial, apical spine. The distal end of the latter is usually armed with a bunch of terminal teeth or bristles. In the similar Sagoscena the internal cavity of the pyramids is simple, without axial rod.
1. Sagenoscena stellata, n. sp. (Pl. [108], fig. 3).
Pyramids rather regular, usually six-sided (intermingled with single five-sided and four-sided forms); their axial rod and its prolongation, the radial apical spine, three to four times as thick as the slender edges of the pyramid. The distal end of the apical spine bears an elegant star of numerous radially divergent terminal branches, each of which is armed with a spinulate terminal knob.
Dimensions.—Diameter of the sphere 3.5 to 4.0, length of the net bars 0.3, breadth 0.003; length of the radial spines 0.2, breadth 0.012.
Habitat.—South Atlantic, Station 318, depth 2040 fathoms.
2. Sagenoscena ornata, n. sp. (Pl. [108], fig. 4).