Page:Scientific results HMS Challenger vol 18 part 2.djvu/340

1216 6. Lampromitra schultzei, Haeckel.

Eucecryphalus schultzei, Haeckel, 1862, Monogr. d. Radiol., p. 309, Taf. v. figs. 16-19.

Shell flat, conical, smooth, with slight collar stricture. Length of the two joints = 1 : 3, breadth = 1 : 8. Cephalis hemispherical, with a small conical horn of half the length, and very small roundish pores. Thorax with three strong, straight ribs and irregular polygonal pores, which are much larger in the middle part than in the upper or lower part. Peristome with a double coronal of short, conical, divergent spines; the superior obliquely ascending, the inferior vertically descending. (Named in honour of the late Professor Max Schultze, the illustrious histologist.)

Dimensions.—Cephalis 0.025 diameter; thorax 0.07 long, 0.2 broad.

Habitat.—Mediterranean, Messina, surface.

7. Lampromitra arborescens, n. sp, (Pl. 60, fig. 8, 8a).

Shell flat, pyramidal, spiny, with sharp collar stricture. Length of the two joints = 1 : 3, breadth = 2 : 10. Cephalis cap-shaped, with an oblique, slender, conical horn of twice the length, and small circular pores. Thorax with three slight almost obliterated ribs and three vaulted sides between them, with irregular roundish pores. The three ribs are distinct in the proximal, not in the distal part. Peristome with a double coronal of smaller squarish pores and numerous divergent spines; the larger spines are irregularly branched and as long as the diameter of the cephalis.

Dimensions.—Cephalis 0.15 long, 0.03 broad; thorax 0.04 long, 0.2 broad.

Habitat.—Indian Ocean, Madagascar (Rabbe), surface.

8. Lampromitra dendrocorona, n. sp. (Pl. 58, fig. 9).

Shell flat, conical, with smooth surface and deep collar stricture. Length of the two joints = 1 : 4, breadth = 2 : 10. Cephalis hemispherical, with a slender occipital horn of three times the length, and a small divergent frontal horn. Thorax with three strong prominent straight ribs and irregular polygonal meshes, increasing in size towards the mouth. Peristome with a dense coronal of numerous short conical spines and twenty-four to thirty larger arborescent spines, longer than the diameter of the cephalis.

Dimensions.—Cephalis 0.02 long, 0.04 broad; thorax 0.08 long, 0.2 broad.

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

Definition.— (vel Dicyrtida triradiata aperta) with three vertical latticed wings, which stretch between the three divergent lateral ribs of the thorax and the vertical horn of the cephalis. No frontal horn.