Page:Scientific results HMS Challenger vol 18 part 1.djvu/256

48 than the geminate-forked, but sometimes the contrary is the case. On their variability compare the general remarks on the genus, and the chapter on "Transformation" in the general introduction.

Dimensions.—Length of the simple spicula 0.05 to 0.1, of the middle rod of the forked spicule 0.05 to 0.08, of their shanks 0.01 to 0.03.

Habitat.—Mediterranean, Naples, Spezzia, surface.

7. Rhaphidozoum patagonicum, n. sp.

Spicula mixed, of two different kinds, simple needles and geminate-triradiate. Simple rods, like those of Belonozoum spinulosum, straight, thorny, pointed at both ends. Geminate spicula double-triradiate, like those of Sphærozoum punctatum, composed of a simple, short, axial rod and three simple pointed shanks on each end of it. Shanks straight, thorny, with many small spinules, commonly somewhat longer than the middle rod. (Often some of the spicula of both kinds are smooth, not thorny, or not straight, but a little curved, or a few forked or four-radiated geminate spicula are mingled with the others.)

Dimensions.—Diameter of the central capsules 0.08 to 0.2, length of the simple spicula 0.1 to 0.15, of the geminate 0.08 to 0.16.

Habitat.—South Pacific, west coast of Patagonia, Station 302, surface.

8. Rhaphidozoum ascensionis, n. sp.

Spicula mixed, of two different kinds, simple needles and geminate-triradiate; both kinds thin, smooth, without spinules. Simple needles somewhat curved, C- or S-shaped. Geminate spicula double-triradiate, composed of a simple, short, straight axial rod and three slender curved shanks on each end of it. Shanks two to four times longer than the middle rod. (Sometimes few simple hexaradiate and geminate tetraradiate spicula are mingled.)

Dimensions.—Diameter of the central capsules 0.12 to 0.15, length of the simple spicula 0.1, of the double-triradiate 0.05 to 0.2.

Habitat.—South Atlantic, off Ascension Island, Station 342, surface.

9. Rhaphidozoum capense, n. sp.

Spicula of two different kinds; one kind simple, needle-shaped, straight, pointed at both ends, the other kind geminate-quadriradiate, with a stout short middle rod and four longer bent shanks on each end of it. Both kinds smooth.

Dimensions.—Diameter of the capsules 0.2 to 0.25, length of the simple needles 0.01 to 0.3, of the geminate spicula 0.05 to 0.15.

Habitat.—Cape of Good Hope (Agulhas), Station 142, surface.

10. Rhaphidozoum australe, n. sp.

Spicula of two different kinds; one kind simple, needle-shaped, curved, thin; the other kind geminate, with a variable number of shanks on both ends of the shorter middle rod, often