Page:Scientific results HMS Challenger vol 18 part 2.djvu/799

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REPORT ON THE RADIOLARIA
1675

long as the six alternate ascending, nearly straight, covered with numerous elegant pencils. Each pencil is richly branched, with fifty to one hundred or more thread-like ramules, and each terminal ramule has two cruciate spathillæ, a larger proximal and a smaller distal (figs. 3, 4); the four recurved anchor-teeth of the proximal spathilla are twice as large as those of the distal. The distal end of each descending foot bears three or four very stout terminal branches, each of which is about as long as the shell and again trifurcate at the distal end.

Dimensions.—Length of the shell 0.2 to 0.3, breadth 0.4 to 0.5.

Habitat.—Tropical Atlantic, Stations 346 to 348, surface.


2. Gorgonetta geryonia, n. sp.

Shell hemispherical, twice as broad as long, with short scattered thorns on the surface. Twelve feet of similar shape to those in the preceding species, but differing in the following characters:—the six ascending feet are much smaller, about as long as the breadth of the shell, and each bears only six to twelve short branches; the six descending feet are about three times as long as the shell, more or less curved; their pencils much smaller, and the two spathillæ of each pencil-thread bear five anchor-teeth. The distal ends are more richly and irregularly branched.

Dimensions.—Length of the shell 0.4, breadth 0.7.

Habitat.—Indian Ocean (Cocos Islands), Rabbe, surface.


3. Gorgonetta carmarina, n. sp.

Shell flat, cap-shaped, three times as broad as long. Twelve feet similar in shape to those of the two preceding species, but more irregular in form and arrangement, and differing in the following characters:—the six ascending feet are nearly horizontally expanded, one and a half times as long as the breadth of the shell, with few short branches, each of which bears a spathilla with six recurved anchor-teeth. The six descending feet are about five times as long as the shell, irregularly curved, studded with numerous small pencils, each thread of which bears a double spathilla with six teeth. The distal ends are irregularly branched.

Dimensions.—Length of the shell 0.2, breadth 0.7.

Habitat.—South Pacific, Station 318, depth 2040 fathoms.


4. Gorgonetta bisenaria, n. sp.

Shell campanulate, similar to that of Gazelletta melusina (Pl. 118, fig. 1), with smooth surface. Six ascending feet about as long as the shell, nearly straight, similar to those of Gorgonetta mirabilis (Pl. 119, fig. 1). Six descending feet also similar to those of the latter, but shorter, about twice as long as the shell, strongly curved, studded with numerous small pencils, each thread of which has a double spathilla with three teeth. The distal end of each foot bears a whorl of six to eight irregular forked branches.

Dimensions.—Length of the shell 0.5, breadth 0.4.

Habitat.—Central Pacific, Station 263, surface.