Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia) / Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII

by Ernst Haeckel

Habitat.—Pacific, central area, Station 266, depth 2750 fathoms.

2. Prunulum cerasum, n. sp.

Cortical shell thick walled, smooth, with circular, hexagonally framed pores, of the same breadth as the bars; sixteen to eighteen on the half equator. Proportion of the two axes of the ellipsoid = 5 : 4. Both medullary shells spherical. (The cortical shell resembles that of Pipetta tuba, Pl. [39], fig. 7, without the polar tubes.)

Dimensions.—Major axis 0.15, minor 0.12; pores and bars 0.007; diameter of the medullary shells 0.08 and 0.04.

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

3. Prunulum amygdalum, n. sp.

Cortical shell thick walled, smooth, with regular, circular, hexagonally lobulated pores, three times as broad as the bars; twelve to fourteen on the half equator (of the same form as in Druppula phœnix and in Stauroxiphos gladius, Pl. [15], fig. 7). Proportion of the two axes = 6 : 5. Inner medullary shell spherical, outer ellipsoidal.

Dimensions.—Major axis 0.12, minor 0.1; pores 0.009, bars 0.003; diameter of the medullary shells 0.07 and 0.04.

Habitat.—Mediterranean (Corfu), surface.

4. Prunulum coccymelium (Pl. [39], fig. 4).