Eucyrtidium auritum, Stöhr, 1880, Palæontogr., vol. xxvi. p. 104, Taf. iv. fig. 7.
Shell subcylindrical, with five sharp strictures. All six joints nearly equal in length; each with four or five transverse rows of small pores. Cephalis small, flat, hemispherical, with two or three small, conical, oblique horns. Mouth of the sixth joint a little constricted.
Dimensions.—Length of the shell (with six joints) 0.12; length of each joint (on an average) 0.02, breadth 0.04 to 0.05.
Habitat.—Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).
4. Artostrobus biseriatus, n. sp.
Shell cylindrical, smooth, with ten to twelve deep strictures. All joints nearly equal in size; each with two transverse rows of small circular pores. Cephalis hemispherical, with a long, bristle-shaped, curved horn.
Dimensions.—Length of the shell (with twelve joints) 0.24; length of each joint 0.02, breadth 0.04.
Habitat.—Tropical Atlantic, Station 348, depth 2450 fathoms.
5. Artostrobus articulatus, n. sp. (Pl. [79], fig. 16).
Shell subcylindrical, with elegant longitudinal ribs and five sharp strictures. All six joints nearly equal in length, each with three or four transverse rows of small circular pores. The middle joints twice as broad as long. Cephalis hemispherical with a conical, oblique horn.