1. Cyphocolpus didymus, n. sp.
Inner cortical shell with circular, subregular pores, twice as broad as the bars; five to six on the half meridian of each chamber, eight to ten on its half equator. Middle cortical shell also with subregular, circular pores of the same size. Outer cortical shell with smooth surface, with more irregular, roundish pores of very different size. The distance between every two shells equals the diameter of the inner medullary shell, which, like the outer, is spheroidal.
Dimensions.—Main axis of the outer cortical shell 0.3, of the middle 0.22, of the inner 0.15; greatest breadth of the inner cortical shell 0.1, its pores 0.01, bars 0.005.
Habitat.—Indian Ocean, Madagascar, Rabbe, surface.
2. Cyphocolpus virginis, n. sp. (Pl. [40], fig. 11).
Zygartus virginis, Haeckel, 1881, Prodromus et Atlas (pl. xl. fig. 11).
Inner cortical shell with irregular, roundish pores, twice to three times as broad as the bars; eleven to twelve on the half meridian of each chamber, sixteen to eighteen on its half equator. Middle cortical shell with very delicate network, its irregular, polygonal pores of the same size as those of the inner, but separated by extremely thin bars. Outer cortical shell with spiny surface, and with more irregular, roundish pores of different size. The distance between each two shells is variable, and attains more than the diameter of the outer medullary shell, which, like the inner, is spheroidal, slightly compressed.
Dimensions.—Main axis of the outer cortical shell 0.26, of the middle 0.22, of the inner 0.14; greatest breadth of the inner cortical shell 0.09, its pores 0.004 to 0.006, bars 0.002.
Habitat.—Pacific, central area, Station 271, surface.