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.—Fossil in Tertiary rocks of Sicily, Grotte (Stöhr), Caltanisetta (Haeckel).

5. Ommatodiscus lævigatus, Stöhr.

Ommatodiscus lævigatus, Stöhr, 1880, Palæontogr., vol. xxvi. p. 116, Taf. vi. figs. 9, 9a.

Disk elliptical (3 : 4), with three chambered rings around the circular central chamber, the third ring half as broad as the second. Chambers twice as high as broad. Pores very small, one-third as broad as the bars. Osculum twice as broad as the central chamber, armed with a crown of short conical teeth.

Dimensions.—Length of the disk 0.15, breadth 0.11; breadth of inner rings 0.02, of the outer 0.01; pores 0.0017.

Habitat.—Fossil in Tertiary rocks of Sicily, Grotte, Stöhr.

6. Ommatodiscus fragilis, Stöhr.

Ommatodiscus fragilis, Stöhr, 1880, Palæontogr., vol. xxvi. p. 116, Taf. vi. figs. 10, 10a.

Disk elliptical (4 : 5), with five chambered rings around the elliptical central chamber, the fifth ring twice as broad as each of the others. Chambers about as high as broad. Pores very small, one-fifth as broad as the bars. Osculum three times as broad as the central chamber, surrounded by a coronet of short teeth.

Dimensions.—Length of the disk 0.17, breadth 0.13; breadth of the inner rings 0.01, of the outer 0.02; pores 0.001.