Cortical shell lentelliptical, one and a fourth times as long as broad, covered with numerous (eighty to one hundred and twenty or more) short, branched radial spines, about half as long as the radius of the shell; each spine once or twice dichotomous, with curved divergent branches. Spiral turnings simple, with gradually increasing breadth, so that the beginning of the third spiral is twice as broad as the first, and as the simple spherical medullary shell.
Dimensions.—Length of the cortical shell (with four spiral convolutions) 0.18, breadth 0.14; diameter of the medullary shell 0.015.
Habitat.—Pacific, central area, Station 274, surface.
Subgenus 2. Drymospira, Haeckel, 1881, Prodromus, p. 464.
Definition.—Spiral convolutions of the cortical shell double.
5. Lithelius solaris, n. sp. (Pl. [49], fig. 2).
Cortical shell spherical, covered with simple, very numerous (two hundred to three hundred) bristle-shaped radial spines, longer than the diameter of the shell. Spiral turnings double, both of the same breadth, gradually increasing with the growth of the shell and several times surpassing the diameter of the simple spherical medullary shell. (Pl. [49], fig. 2, exhibits only the first convolutions in the centre of the shell.)
Dimensions.—Diameter of the cortical shell (with four spiral convolutions) 0.18; diameter of the medullary shell 0.02.
Habitat.—Pacific, central area, Stations 266 to 272, surface and in various depths.
6. Lithelius arborescens, n. sp.