2. Cœlacantha mammillata, n. sp.
Internal shell strongly mammillate, with sixty to eighty radial rods, which are densely studded with cruciate verticils of quadridentate anchor-threads. External shell with irregular, mostly hexagonal meshes, the bars of which bear the same verticils, each composed of four thin quadridentate anchor-threads. At each nodal point arises a slender, smooth, radial spine, which bears at its distal end a verticil of four large, curved, terminal branches.
Dimensions.—Diameter of the inner shell 0.4, of the outer 3.2.
Habitat.—South Atlantic, Station 332, depth 2200 fathoms.
Order III. PHÆOGROMIA, Haeckel, 1879.
Definition.—Phæodaria with a simple, not bivalved lattice-shell, which assumes very different forms, but is always provided with a peculiar mouth and peristome on the oral pole of the main axis. Central capsule always excentric, placed in the aboral half of the shell-cavity.
Family LXXVIII. Challengerida, John Murray (Pl. [99]).
Challengerida, John Murray, 1876, Proc. Roy. Soc. Lond., vol. xxiv. p. 471, pl. xxiv. figs. 1, 2.
Definition.—Phæodaria with a monaxonial, usually ovate or lenticular shell, which exhibits a peculiar, fine, regularly hexagonal, diatomaceous structure, and is usually provided with teeth on the mouth, but without articulated feet. Central capsule excentric, placed in the aboral half of the shell-cavity.