Page:Scientific results HMS Challenger vol 18 part 2.djvu/631

Rh 16. Lithocampe meta, Stöhr.

Lithocampe meta, Stöhr, 1880, Palæontogr., vol. xxvi. p. 103, Taf. iv. fig. 4.

Shell rough, subconical, obtuse, with four slight strictures. Five joints of different lengths = 2 : 4 : 5 : 4 : 2. The fourth joint is the broadest, and three times as broad as the constricted mouth. Pores, small, regular, circular, quincuncially disposed, equal in size; two transverse rows in the first and fifth, five rows in the second and fourth, six rows in the third joint.

Dimensions.—Length of the shell (with five joints) 0.14. Length of the single joints, a 0.017, b 0.033, c 0.04, d 0.033, e 0.017; greatest breadth 0.083.

Habitat.—Fossil in Tertiary rocks of Sicily, Grotte (Stöhr), Caltanisetta (Haeckel).

17. Lithocampe urceolata, n. sp. (Pl. 77, fig. 2).

Shell rough, wide, urceolate, without external strictures, but with four internal septal rings (not visible in the figure), each of which contains an internal circle of horizontal pores. Five joints of different lengths = 2 : 3 : 6 : 4 : 2. The third joint is the broadest, and three times as broad as the constricted mouth. Pores of very different sizes, irregular, roundish, with prominent polygonal frames. A very remarkable species.

Dimensions.—Length of the shell (with five joints) 0.17. Length of the single joints, a 0.02, b 0.03, c 0.06, d 0.04, e 0.02; greatest breadth 0.13.

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

18. Lithocampe clava, Ehrenberg.

Lithocampe clava, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. iv. fig. 2.

Shell smooth, club-shaped, or slenderly ovate, with five internal septal rings. Six joints of very different lengths = 5 : 2 : 3 : 4 : 5 : 18. The sixth joint is the broadest, and as long as the five others together. Pores small, circular, in the basal half of the last joint irregular and larger. Constricted mouth as broad as the subspherical, hyaline cephalis.

Dimensions.—Length of the shell (with six joints) 0.15. Length of the single joints, a 0.02, b 0.011, c 0.013, d 0.016, e 0.02, f 0.07.

Habitat.—Fossil in Barbados.

19. Lithocampe hexacola, n. sp. (Pl. 79, fig. 7).

Shell smooth, nearly spindle-shaped, without external strictures, but with five internal septal rings. Six joints of different lengths = 4 : 8 : 5 : 5 : 5 : 10. The fourth joint is the broadest, and four times as broad as the constricted mouth. Pores subregular hexagonal, or irregular polygonal, with thin bars.

Dimensions.—Length of the shell (with six joints) 0.18, greatest breadth 0.09. Length of the six joints, a 0.02, b 0.04, c, d, and e each 0.025, f 0.05.

Habitat.—Central Pacific, Station 271, depth 2425 fathoms.