Page:Scientific results HMS Challenger vol 18 part 1.djvu/253

Rh Dimensions.—Diameter of the capsules 0.16 to 0.18, length of the spicula 0.1 to 0.2.

Habitat.—South Atlantic (Tristan da Cunha), Station 332, surface.

Definition.—Spicula all geminate-radiate, but with a different and variable number of shanks on each end of the middle rod.

17. Sphærozoum stellatum, n. sp.

Spicula all geminate-radiate, with a strong middle rod and a variable number of shorter radiating shanks on the two ends of it. Shanks straight, nearly conical, smooth; for the most part three or four shanks on each end, but sometimes also five or six; very often this number is unequal on the two ends.

Dimensions.—Diameter of the central capsules 0.1 to 0.2, length of the spicula 0.05 to 0.15.

Habitat.—Central Pacific, Station 270, surface.

18. Sphærozoum geminatum, n. sp. (Pl. 4, fig. 4).

Spicula all geminate-radiate, with a strong middle rod and a variable number of longer radiant shanks on each end of it. Shanks straight, conical, in the distal half thorny; commonly either three or four shanks on each end of the middle rod, often also three on one end, four on the other end; rarely five or six rays on one end.

Dimensions.—Diameter of the capsules 0.15 to 0.2, length of the spicula 0.05 to 0.1.

Habitat.—Indian Ocean, Ceylon, Haeckel; surface.

19. Sphærozoum circumtextum, n. sp.

Spicula all geminate-radiate, with a very variable number of rays (two to six) on each end of the thin middle rod. All spicula very thin and delicate, smooth, with curved or bent shanks, densely covering the central capsule like a cobweb. The number of rays on each end is usually different, generally four or five, often also two or three, rarely six.

Dimensions.—Diameter of the capsule 0.1 to 0.2, length of the spicula 0.04 to 0.12.

Habitat.—Southeast part of the Indian Ocean, Station 160, surface.

20. Sphærozoum variabile, n. sp. (Pl. 4, fig. 5).

Spicula all geminate-radiate, with a short middle rod and a variable number of shanks on each end of it. Shanks four to eight times as long as the middle rod, curved or bent, in the distal half thorny; their number is commonly different on the two ends of it, three or five, often also four or six, rarely two; their size and form very variable.