Page:Scientific results HMS Challenger vol 18 part 2.djvu/831

Rh the shell. The tubular peristome is about half as long as the shell, bottle-shaped, nearly three-sided prismatic, and bears three very long spinulate teeth, which in the lower half are parallel, in the upper slightly curved and diverging, at the base pear-shaped. Three ovate basal pores in the inflated base of each foot and each tooth.

Dimensions.—Length of the shell 2.5, breadth 1.5.

Habitat.—South Pacific, Station 295, depth 1500 fathoms.

3. Tuscarora wyvillei, n. sp. (Pl. 100, figs. 3, 3a-3c).

Shell subspherical, pellucid, thinner and more fragile than in the other species of the genus, with three aboral perradial feet in the lower third, and three interradial teeth around the wide mouth. The three feet are straight, conical, widely divergent, shorter than the shell, and arise from its lower third; on the inflated base of each four small ovate pores. The three teeth, alternating with them, are straight, cylindrical, arise from the margin of the mouth and diverge obliquely upwards. On the base of each foot four opposite cordate pores of very unequal size.

Dimensions.—Length of the shell 1.5, breadth 1.4.

Habitat.—South Pacific, Station 291, depth 2250 fathoms.

4. Tuscarora tetrahedra, John Murray (Pl. 100, figs. 4, 4a).

Tuscarora tetrahedra, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pl. A, fig. 19.

Shell tetrahedral or three-sided pyramidal, with three perradial basal feet, and three alternate, interradial, circoral teeth. The three rounded edges of the pyramid are prolonged directly over the aboral base into the three short, divergent, conical, basal feet, which are smooth and scarcely one-fourth as long as the shell. The base of each foot is pierced by four small crossed pedal pores. The narrow mouth, on the apex of the pyramid, is surrounded by three short and broad, triangular, spinulate teeth, each of which bears three slender, triangular, dental pores.

Dimensions.—Length of the shell 2.5, breadth 2.0.

Habitat.—Tropical Atlantic, Station 348, depth 2450 fathoms.

Definition.—Shell with three perradial equidistant feet, and with two circoral teeth, which are opposite in the radius of the odd dorsal foot; therefore a dorsal and a ventral tooth.

5. Tuscarora tubulosa, John Murray (Pl. 100, figs. 5, 5a, 5b).

Tuscarora tubulosa, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pl. A, fig. 17.

Shell subspherical, with three lateral perradial feet on the upper half of the shell (above the equator), and two parallel vertical teeth on the mouth. The three feet arise between the upper and