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.—Central Pacific, Stations 272 to 274, surface.

3. Heliodiscus trigonodon, n. sp.

Disk with smooth surface, four times as broad as the medullary shell. Pores regular, circular; eighteen to twenty on the radius. Marginal spines sixteen to twenty, equilateral triangular, flat, smooth, about as long and broad as the radius of the medullary shell.

Dimensions.—Diameter of the disk 0.2, of the medullary shell 0.05; length of the radial spines 0.03, basal breadth 0.03.

Habitat.—Central Pacific, Stations 266 to 274, depths 2350 to 2925 fathoms.

4. Heliodiscus glyphodon, n. sp. (Pl. [35], fig. 2).

Heliosestrum glyphodon, Haeckel, 1881, Prodromus et Atlas (pl. xxxv. fig. 2).

Disk with smooth surface, four times as broad as the medullary shell. Pores subregular, circular; seven to eight on the radius. Marginal spines ten to twelve, equilateral triangular, flat, deeply furrowed, twice as long as broad, and as long as the radius of the disk.

Dimensions.—Diameter of the disk 0.14, of the medullary shell 0.035; length of the radial spines 0.07, basal breadth 0.035.

Habitat.—North Pacific, Station 253, depth 3125 fathoms.