Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Second Part: Subclass Osculosa; Index / Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII

by Ernst Haeckel

Dimensions.—Diameter of the gate 0.08; thickness of the ring 0.012.

Habitat.—North Atlantic, surface (Rabbe).

9. Archicircus primordialis, n. sp. (Pl. [81], fig. 1).

Gate ovate. Ring hexagonal, with three prominent edges and six short pyramidal thorns at the six corners; the basal thorn is either simple or forked.

Dimensions.—Diameter of the gate 0.07; thickness of the ring 0.01 to 0.015.

Habitat.—Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

10. Archicircus hexacanthus, n. sp. (Pl. [81], fig. 4).

Gate subregular, hexagonal. Ring hexagonal, with three sharp edges and six equal radial pyramidal spines, arising from the six corners and placed in the plane of the ring, about as long as the diameter of the gate.

Dimensions.—Diameter of the gate 0.05 to 0.07; thickness of the ring 0.01.

Habitat.—South Pacific, Station 295, depth 1500 fathoms.