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

Dimensions.—Diameter of the disk 0.2, of the outer meshes 0.008 to 0.012, of the inner meshes 0.002 to 0.003.

Habitat.—North Atlantic, Greenland, Færöe Channel (John Murray), surface.

5. Spongodiscus biconcavus, n. sp.

Spongy disk biconcave, in the peripheral, ring-like, thickened part twice as thick as in the hollowed central part, with an irregular framework, without concentric rings. Texture different, in the outer half looser than in the inner, darker part; meshes of the outer part five to six times, of the inner twice to three times, as broad as the bars.

Dimensions.—Diameter of the disk 0.25, of the outer meshes 0.01 to 0.012, of the inner 0.004 to 0.006.

Habitat.—Pacific, central area, Station 265, depth 2900 fathoms.

Subgenus 2. Spongocyclia, Haeckel, 1862, Monogr. d. Radiol., p. 469.

Definition.—Spongy framework of the disk in the inner part with concentric, circular rings, in the outer part irregular.

6. Spongodiscus cycloides, Haeckel.

Spongodiscus cycloides, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 843.