Page:Scientific results HMS Challenger vol 18 part 1.djvu/860

652 7. Octopyle tetrastyle, n. sp.

Cortical shell lentelliptical, with rough surface and four angular radial spines in the lateral plane, opposite in pairs in two crossed diagonals. Lateral girdle nearly rectangular (each angle with one spine), one and a third times as long as broad. Sagittal septum longer than the hexagonal medullary shell. Eight gates egg-shaped.

Dimensions.—Length of the medullary shell 0.05, breadth 0.03; length of the cortical shell 0.16, breadth 0.12.

Habitat.—North Atlantic, Station 354, surface.

8. Octopyle tetraptera, n. sp.

Cortical shell quadrangular, with thorny surface and four latticed wing-like prolongations on the corners of the quadrangle, opposite in pairs in two crossed diagonals, each wing supported by a strong radial spine. Lateral girdle quadrangular, one and a half times as long as broad. On the isthmus of the transverse girdle four pores. Sagittal septum longer than the hexagonal medullary shell. Eight gates triangular.

Dimensions.—Length of the medullary shell 0.07, breadth 0.04; length of the cortical shell 0.24, breadth 0.16.

Habitat.—Pacific, central area, Station 271, surface.

9. Octopyle stenozona, n. sp. (Pl. 9, fig. 11).

Cortical shell quadrangular, with thorny surface, and four conical spines in the lateral plane, on the points, where both cortical girdles are crossed. Lateral girdle very narrow, nearly square, with rounded corners, of equal length and breadth. On the isthmus of the narrow transverse girdle only one pore. Sagittal septum of the same length as the subspherical medullary shell. Eight gates irregular roundish or nearly circular.

Dimensions.—Diameter of the medullary shell 0.04, of the cortical shell 0.14.

Habitat.—Tropical Atlantic, Station 338, depth 1990 fathoms.

10. Octopyle euryzona, n. sp.

Cortical shell nearly quadrangular, very thorny, with four bunches of stronger radial spines on the four corners. Lateral girdle broad, with rounded edges of the quadrangle, little longer than broad. On the isthmus of the broad transverse girdle four pores. Sagittal septum of the same length as the elliptical medullary shell, with many radial beams. Eight gates nearly square.

Dimensions.—Length of the medullary shell 0.05, breadth 0.035; length of the cortical shell 0.16, breadth 0.14.

Habitat.—Southern Atlantic, Station 332, depth 2200 fathoms.