Habitat.—South Pacific, Station 288, surface.
14. Octopyle obtecta, n. sp.
Cortical shell quadrangular, thorny, with eight strong diagonal spines, lying in two crossed planes, and arising from the proximal edges of the gates in the same way as in the foregoing species. It differs from this by four prominent latticed roofs, which arise from the distal edge of the gates and connect the diagonal spines of one gate. Octopyle obtecta bears therefore the same relation to Octopyle octostyle that Tetrapyle pluteus does to Tetrapyle octacantha.
Dimensions.—Length of the medullary shell 0.055, breadth 0.04; length of the cortical shell 0.16, breadth 0.12.
Habitat.—Indian Ocean, surface, Madagascar, Rabbe.
15. Octopyle decastyle, n. sp. (Pl. [9], fig. 13).
Cortical shell thorny, nearly quadrangular, with ten stronger radial spines, two opposite on the poles of the principal axis (as prolongations of the axial beams), eight others opposite in pairs in two diagonal planes (as in the foregoing species). Lateral girdle nearly square, with slightly convex lateral faces, slightly concave principal faces. Transverse girdle broad, with four pores on the isthmus. Sagittal septum of the same length as the hexagonal medullary shell. Eight gates elliptical or irregular roundish.
Dimensions.—Length of the medullary shell 0.05, breadth 0.032; diameter of the cortical shell 0.15.
Habitat.—Western Tropical Pacific, Station 224, depth 1850 fathoms.