Page:Scientific results HMS Challenger vol 18 part 1.djvu/275

Rh outer half, sieve-shaped. Pores one to three times as broad as the bars, of very different size, four to six on the quadrant.

Dimensions.—Diameter of the shell 0.15, pores 0.01 to 0.02, bars 0.005 to 0.01.

Habitat.—Tropical Atlantic, Station 347, depth 2250 fathoms.

29. Cenosphæra coronata, n. sp. (Pl. 26, fig. 11).

Shell thick walled, rough. Pores irregular, roundish, surrounded by high polygonal frames bearing on their sharp crest a series of small papillæ, so that each pore is surrounded by a coronal of such spinules. Pores four to eight times as broad as the bars, four to five on the quadrant.

Dimensions.—Diameter of the shell 0.15, pores 0.01 to 0.03, bars 0.002 to 0.008.

Habitat.—Central Pacific, Station 272, depth 2600 fathoms.

Definition.—Pores of the spherical shell irregular, roundish, without polygonal frames, of unequal size or form.

30. Cenosphæra antiqua, Haeckel.

Cenosphæra plutonis, var., Dunikowski, 1882, Denkschr. d. k. Akad. d. Wiss. Wien, Bd. xlv. p. 25, Taf. iv. figs. 47, 48.

Cenosphæra plutonis, var., Stöhr, 1880, Palæontogr. xxvi. p. 85, Taf. i. fig. 1.

Shell thin walled, smooth. Pores irregular, roundish, two to eight times as broad as the bars, ten to fifteen on the quadrant.

Dimensions.—Diameter of the shell 0.15 to 0.2, pores 0.007 to 0.015, bars 0.002 to 0.008.

Habitat.—Fossil in the Jurassic, Cretaceous, and Tertiary formations; living in the depths of the Atlantic and Pacific; Station 332, depth 2200 fathoms; Station 225, depth 4475 fathoms, &c.

31. Cenosphæra gigantea, n. sp.

Shell thick walled, smooth. Pores irregular, roundish, two to five times as broad as the bars, thirty to forty on the quadrant.

Dimensions.—Diameter of the shell 0.4 to 0.5, pores 0.004 to 0.01, bars 0.002.

Habitat.—Central Pacific, Station 268, depth 2900 fathoms; also fossil in Barbados.

32. Cenosphæra marginata, n. sp.

Shell very thick walled, smooth. Pores irregular, roundish, double-edged, three to eight times as broad as the bars, six to eight on the quadrant.