Page:Scientific results HMS Challenger vol 18 part 2.djvu/602

1478 each of the following joints; in each of the former three to four transverse rows, in each of the latter six to eight transverse rows of small, regular, circular pores.

Dimensions.—Length of the shell (with six joints) 0.09, of the three first joints 0.03, of the three following 0.06; breadth of the sixth joint 0.08, of the fourth 0.04.

Habitat.—Mediterranean (Candia) Spratt, depth 1620 fathoms.

7. Dictyomitra demersissima, Haeckel.

Eucyrtidium demersissimum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291, Taf. vii. fig. 11.

Shell slender, conical, smooth, with four internal septal rings (without external strictures). Breadth of the five joints gradually increasing, length unequal; the third joint the longest, twice as long as the second, and longer than any of the following. Pores very small and numerous, in longitudinal rows.

Dimensions.—Length of the shell (with five joints) 0.09, of the second joint 0.015, of the third 0.03; breadth of the second joint 0.03, of the third 0.05.

Habitat.—Tropical Pacific, Philippine Sea, depth 3300 fathoms.

Definition.—Shell with longitudinal ribs and furrows between them, with joints of different lengths.

8. Dictyomitra costata, n. sp.

Shell slender, conical, with prominent longitudinal ribs, and six to eight deep strictures. Length of the majority of joints nearly equal, the two or three first joints shorter, the last a little longer. In each joint only a single transverse series of pores at the distal end (one pore in each furrow). (Similar to Siphocampe tubulosa, Pl. 79, fig. 13, but conical, and without cephalic tube.)

Dimensions.—Length of the shell (with eight joints) 0.16, of each middle joint 0.03, of the first 0.02; breadth of the last joint 0.06.

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

9. Dictyomitra multicostata, Zittel.

Dictyomitra multicostata, Zittel, 1876, Zeitschr. d. deutsch. geol. Gesellsch., p. 81, Taf. ii. figs. 2-4.

Shell slender, conical, with prominent longitudinal ribs, and eight to ten deep strictures. Length and breadth of the joints gradually increasing, the eighth joint twice as long and broad as the fourth joint. Pores regular, circular, one series in each longitudinal furrow, three to four pores on each joint.