Page:Scientific results HMS Challenger vol 18 part 1.djvu/436

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
228
THE VOYAGE OF THE H.M.S. CHALLENGER.

The genus Elaphococcus differs from the preceding Cladococcus in the mode of ramification of the radial spines. These are forked; and the forked branches are either simple, again forked, or dichotomously ramified.


Subgenus 1. Elaphococcinus, Haeckel.

Definition.—Pores of the shell regular, of nearly equal size and similar form.


1. Elaphococcus furcatus, n. sp.

Pores of the spherical shell regular, hexagonal, four times as broad as the bars; four to five on the radius. Radial spines, arising from all the nodal-points of the network, cylindrical, as long as the radius, simply forked at the distal end; both branches half as long as the undivided part.

Dimensions.—Diameter of the shell 0.08, pores 0.01, bars 0.0025; length of the spines 0.04, breadth 0.004.

Habitat.—Tropical Atlantic, Station 348, surface.


2. Elaphococcus cervicornis, Haeckel.

Cladococcus cervicornis, Haeckel, 1862, Monogr. d. Radiol., p. 370, Taf. xiv. figs. 4-6.

Pores regular, hexagonal, ten to twenty times as broad as the bars; five to seven on the radius. Fifty to ninety radial spines (or more), arising not only from the nodal-points of the network but also from the bars between them. Each spine is cylindrical, longer than the shell diameter, and repeatedly forked (three to six times), having, therefore, numerous (thirty to sixty or more) curved branches. The distal ends of all branches fall in one spherical face.

Dimensions.—Diameter of the shell 0.07 to 0.09, pores 0.01 to 0.015, bars 0.001 to 0.015; length of the spines 0.1 to 0.15, breadth 0.005.

Habitat.—Cosmopolitan; Mediterranean, Atlantic, Indian, Pacific, surface.


3. Elaphococcus elaphoceras, n. sp.

Pores regular, circular, hexagonally framed, three to four times as broad as the bars; six to eight on the radius. At each nodal-point of the hexagon arises a short bristle-shaped, simple by-spine. In addition, there arise from the bars thirty to sixty large main spines, longer than the shell diameter, repeatedly forked in the same way as in the preceding species.

Dimensions.—Diameter of the shell 0.1, pores 0.008, bars 0.002; length of the spines 0.12, breadth 0.002.

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


4. Elaphococcus umbellifer, n. sp.

Pores regular, circular, three times as broad as the bars; ten to twelve on the radius. Twenty to forty straight cylindrical spines, as long as the shell diameter, having at the distal end a regular