Page:Scientific results HMS Challenger vol 18 part 1.djvu/305

Rh meshes) on the thinner end of the ovate shell (corresponding to the insertion of a pear-stalk); sometimes two or three such large openings.

Dimensions.—Diameter of the shell 0.1 to 0.15, of the pores 0.008 to 0.016, of the bridges 0.004 to 0.008.

Habitat.—Tropical zone—Cape Verde Islands, Ceylon; Central Pacific, Stations 266 to 272, 348 to 352, &c.

7. Collosphæra polyedra, n. sp.

Trisolenia zanguebarica, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 301, Taf. x. fig. 11.

Shell irregular, polyhedral, with even or somewhat vaulted sides, and obtuse ridges between them. Network more or less irregular, with small rounded meshes, quite as broad or twice as broad as their bars. Besides these small pores constantly some large round openings (commonly three to six), situated on the corners of the polyhedral shell, four to six times as large as the pores. Often an acute tooth on the edge of each large opening. Transition-form between Collosphæra and Solenosphæra or Odontosphæra.

Dimensions.—Diameter of the shell 0.1 to 0.15, of the pores 0.004 to 0.008, of their bridges 0.004, of the large openings 0.24 to 0.032.

Habitat.—Tropical zone of the Pacific and the Indian Ocean; Stations 266 to 272, surface.

8. Collosphæra tuberosa, n. sp.

Collosphæra huxleyi, var., Haeckel, 1862, Monogr. d. Radiol., Taf. xxxiv. figs. 3, 9.

Shell very irregular, between subspherical and polyhedral in form, but always with irregular impressions, boils or bosses, and between these different rounded prominent tubercles and ridges. Network irregular, strong, with rounded, subcircular or nearly polygonal meshes. Ten to thirty pores in the half meridian of the shell. Diameter of the meshes half to four times as broad as that of the thick bars.

Dimensions.—Diameter of the shell very variable in the same cœnobium, 0.05 to 0.2, of the pores 0.002 to 0.008, breadth of the bridges 0.004 to 0.006.

Habitat.—Cosmopolitan, common in all warmer seas, surface.

9. Collosphæra irregularis, n. sp.

Collosphæra huxleyi, var., Haeckel, 1862, Monogr. d. Radiol., Taf. xxxiv. fig. 8.

Shell quite irregular, knotty or bulbous, with irregular impressions, and prominent knobs or bulbs between them. Network thin, fragile, quite irregular, with polygonal meshes of most unequal size and form. Five to twenty pores in the half meridian of the shell. Diameter of the meshes two to ten times as broad as that of the thin bars.

Dimensions.—Diameter of the shell very variable in the same cœnobium, 0.04 to 0.24, of the pores 0.005 to 0.05, of the bridges 0.002 to 0.004.

Habitat.—Mediterranean, Atlantic, not common; Stations 348, 352, &c., surface.