Network more or less irregular, with unequal triangular meshes. Bars of the network studded with scattered, rectangular, minute crosses, arising perpendicularly, each cross composed of four small equal bars. Nodal points partly solid, partly pierced by a hole. Network very similar to that of Dictyosoma trigonizon, figured in my Monograph, Taf. xxvi. figs. 4, 5.
Dimensions.—Diameter of the shell 1.5, length of the bars 0.1 to 0.2, breadth 0.003.
Habitat.—Mediterranean, Atlantic, Canary Islands, Station 353, surface.
Genus 676. Sagosphæra,[[295]] n. gen.
Definition.—Sagosphærida with a delicate spherical shell, the thin wall of which is composed of a simple lattice-plate, and bears on its nodal points radial spines.
The genus Sagosphæra differs from the preceding Sagena, its ancestral form, in the development of radial spines on the nodal points of the simple delicate lattice-sphere. It exhibits therefore the same relation to the latter as Aulosphæra bears to Aularia. The regular or subregular triangular meshes of the lattice-sphere are separated in Sagosphæra by solid, very thin threads, in the similar Aulosphæra, however, by thicker hollow tubes. The genus Sagosphæra may be divided into two subgenera:—Sagosphærella with a single radial spine at each nodal point of the network, and Sagosphæroma with a bunch of two to four or more divergent radial spines.
1. Sagosphæra trigonilla, n. sp.
Radial spines simple, straight, smooth, about as long as the smooth bars of the network, a single one at each nodal point. Meshes very regular, of equal size, equilateral triangular. (Similar to the common Aulosphæra trigonopa.)
Dimensions.—Diameter of the sphere 1.2 to 1.8, length of the bars 0.1 to 0.2, breadth 0.002 to 0.006.
Habitat.—Cosmopolitan; Mediterranean, Atlantic, Pacific, surface.