Definition.—Network of the shell irregular, with pores of different size or form.
4. Ellipsoxiphus claviger, n. sp. (Pl. [14], fig. 3).
Xiphosphæra clavigera, Haeckel, 1881, Prodromus et Atlas.
Proportion of the major axis to the minor = 5 : 4. Shell thick walled, with irregular network; meshes roundish or circular, double contoured, of unequal size, twice to four times as broad as the bars; eight to ten on the half equator. Polar spines club-shaped, with prominent edges, about as long as the minor axis; thicker in their middle part than at both ends (differs from Xiphosphæra clavigera by the ellipsoidal form of the shell, and the double length of the spines).
Dimensions.—Longer axis 0.15. shorter axis 0.12; pores 0.007 to 0.015, bars 0.004; length of the polar spines 0.12, thickness in the middle part 0.02.
Habitat.—Central area of the Pacific, Station 272, depth 2600 fathoms.
5. Ellipsoxiphus suessi, Dunikowski.
Ellipsoxiphus suessi, Dunikowski, 1882, Denkschr. d. k. Akad. d. Wiss. Wien, Bd. xlv. p. 26, Taf. v. fig. 50.
Proportion of the major axis to the minor = 7 : 5. Shell thick walled, with irregular, roundish meshes, six to eight on the half equator, twice to three times as broad as the bars. Polar spines nearly cylindrical, blunt, as long as the major axis.
Dimensions.—Longer axis 0.14; shorter axis 0.1; pores 0.018 to 0.023, bars 0.01; length of the polar spines 0.12; thickness of them 0.035.