Subgenus 1. Artiscium, Haeckel.
Definition.—Surface of the shell smooth or rough, without radial rods or spines.
1. Artiscus paniscus, n. sp.
Pores of the shell regular, hexagonal, four times as broad as the bars; ten to twelve pores on the half meridian, eight to nine on the half equator. Surface smooth. (The network of this species is quite the same as that of the proximal cameræ of Panartus diploconus, Pl. [40], fig. 1.)
Dimensions.—Main axis of the shell 0.12, equatorial axis 0.07; meshes 0.013, bars 0.003.
Habitat.—Pacific, central area, Station 271, depth 2425.
2. Artiscus facetus, n. sp.
Pores of the shell regular, circular, with prominent hexagonal frame, twice as broad as the bars; twenty-two to twenty-four pores on the half meridian, fourteen to fifteen on the half equator. Surface a little thorny. (The shell of this species exhibits nearly the same formation as that of Cyphonium virgineum, Pl. [39], fig. 12, but without enclosed medullary shells.)
Dimensions.—Main axis of the shell 0.15, equatorial axis 0.09; meshes 0.01, bars 0.005.
Habitat.—Pacific, central area, Station 266, depth 2750 fathoms.