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

4. Archicircus ovalis, n. sp.

Gate ovate. Ring elliptical, smooth, with three prominent, slightly distorted edges, without thorns; in the transverse section triangular.

Dimensions.—Diameter of the gate 0.08 to 0.12; thickness of the ring 0.006 to 0.009.

Habitat.—Tropical Atlantic, Station 347, depth 2250 fathoms.

5. Archicircus monopylus, n. sp.

Gate ovate. Ring ovate, thorny, with three distorted edges, in the transverse section triangular; surface covered with numerous simple small thorns arising from the three edges.

Dimensions.—Diameter of the gate 0.1 to 0.15; thickness of the ring 0.01 to 0.012.

Habitat.—Indian Ocean (Madagascar), Rabbe, surface.

Subgenus 2. Archistephus, Haeckel.

Definition.—Ring polygonal, with four to six or more prominent corners (and commonly with simple spines arising from the corners).