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.—Radius of the arms 0.18, basal breadth 0.03, distal breadth 0.015.

Habitat.—South Pacific, Station 295, depth 1500 fathoms.

Subgenus 2. Spongasterisculus, Haeckel.

Definition.—Cross formed by the four arms, bilateral or irregular, with the arms at different distances.

6. Spongasteriscus quadricornis, Haeckel.

Spongasteriscus quadricornis, Haeckel, 1862, Monogr. d. Radiol., p. 474, Taf. xxviii. figs. 8-10.

Spongodiscus quadricornis, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 844.

Arms at different distances, forming a bilateral or irregular cross, grouped in two opposite pairs; their form equilateral triangular; their length smaller than the radius of the large circular central disk, which exhibits in the interior eight to sixteen concentric rings.

Dimensions.—Radius of the arms 0.2, of the central disk 0.13; basal breadth of the arms 0.08.

Habitat.—Mediterranean (Messina), Haeckel, surface.