Page:Scientific results HMS Challenger vol 18 part 2.djvu/138

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1014
THE VOYAGE OF THE H.M.S. CHALLENGER.

2. Eutympanium octonarium, n. sp.

Eight vertical columellæ slightly curved, thorny. Both horizontal rings equal, octagonal, each armed with eight large, irregularly-branched spines, which on the mitral ring are directed obliquely upwards, on the basal ring downwards.

Dimensions.—Height of the shell 0.12, breadth 0.1.

Habitat.—Central Pacific, Station 268, depth 2900 fathoms.


3. Eutympanium coronarium, n. sp.

Eight thorny columellæ, obliquely descending and curved like a bow, divergent in the upper part, convergent in the lower. Basal ring circular, mitral ring octagonal. Both horizontal rings armed with eight stout thorny spines, which on the mitral ring are smaller and directed obliquely upwards, on the basal ring larger and directed downwards, each with a recurved hook.

Dimensions.—Height of the shell 0.08, breadth 0.06.

Habitat.—South Atlantic, Station 332, depth 2200 fathoms.


4. Eutympanium militare, n. sp. (Pl. 82, fig. 11).

Ten parallel and vertical columellæ straight and smooth, cylindrical. Both horizontal rings equal, circular, armed with numerous short conical spines, divergent in all directions. Ten to twenty spines on each ring larger than the others.

Dimensions.—Height of the shell 0.1, breadth, 0.08.

Habitat.—Western Tropical Pacific, Station 225, depth 4475 fathoms.


5. Eutympanium dodecarium, n. sp.

Twelve vertical columellæ, slightly curved, smooth. Mitral and basal rings circular, both horizontal rings armed with twelve stout, irregularly-branched spines, which are prolongations of the columellæ, and on the mitral ring directed upwards, on the basal ring downwards.

Dimensions.—Height of the shell 0.13, breadth 0.1.

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