Page:Scientific results HMS Challenger vol 18 part 2.djvu/416

1292 concave outlines, and subregular, hexagonal pores, gradually increasing towards the mouth, the largest half as broad as the cephalis. This elegant species is dedicated to Dr. Ray, the discoverer of many rare Radiolarians in the Challenger collection.

Dimensions.—Cephalis 0.03 long, 0.02 broad; thorax 0.08 long, 0.12 broad.

Habitat.—Central Pacific, Stations 266 to 272, surface.

7. Sethoconus cervus, Haeckel.

? Eucyrtidium cervus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291, Taf. ix. fig. 21.

Conarachnium cervus, Haeckel, 1881, Prodromus, p. 430.

Cephalis subspherical, with slight collar stricture, small circular pores, and two to four divergent horns, one or two of which are forked. Thorax wide, conical, about as long as broad, with straight outlines and irregular, polygonal pores, gradually increasing towards the mouth; the largest as broad as the cephalis.

Dimensions.—Cephalis 0.015 long, 0.02 broad; thorax 0.08 long, 0.08 broad.

Habitat.—Indian Ocean; Maldive Islands, surface (Haeckel); Zanzibar, depth 2200 fathoms (Pullen).

8. Sethoconus lophophæna, n. sp.

Conarachnium lophophæna, Haeckel, 1881, Prodromus, p. 430.

Cephalis subspherical, with distinct collar stricture, small circular pores, and numerous (twelve to sixteen) radial, bristle-shaped horns of different lengths. Thorax wide, conical, somewhat longer than broad, with slightly convex outlines, and subregular, hexagonal pores, increasing gradually in size towards the mouth; the largest twice as broad as the cephalis.

Dimensions.—Cephalis 0.03 long, 0.04 broad; thorax 0.2 long, 0.16 broad.

Habitat.—South Pacific, Station 300, depth 1375 fathoms.

9. Sethoconus larvatus, Haeckel.

Lophophæna larvata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. viii. fig. 10.

Dictyocephalus larvatus, Bütschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi. p. 535.

Cephalis subspherical, large, with sharp collar stricture, and numerous (five to ten or more) radial, conical (partly forked) horns of different lengths. Thorax wide, conical, somewhat broader than long, with straight outlines. Pores of both joints very irregular, roundish, of very different sizes and form.

Dimensions.—Cephalis 0.04 long, 0.05 broad; thorax 0.1 long, 0.12 broad.

Habitat.—Fossil in Barbados.