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

Subgenus 1. Eucollosphæra, Haeckel.

Definition.—Shell a regular or subregular sphere.

1. Collosphæra primordialis, n. sp.

Shell a regular sphere, with very delicate and regular network of hexagonal meshes. Six to eight meshes in the half meridian of the shell. Diameter of the meshes ten to fifteen times as broad as the thin bars between them. Can be regarded as social form of Cenosphæra primordialis.

Dimensions.—Diameter of the shell 0.1 to 0.12, of the pores 0.008.

Habitat.—Central Pacific, Stations 271 to 274, surface.

2. Collosphæra regularis, n. sp.

Shell a regular sphere, with a perfectly regular network of circular meshes, all of the same size. Ten to twelve meshes in the half meridian of the shell. Diameter of the meshes the same as that of the bars between them.

Dimensions.—Diameter of the shell 0.1 to 0.12, of the pores 0.005 to 0.006.

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