and the last joints are the longest, the third is the broadest. Mouth slightly constricted (broken off in Stöhr's figure). Cephalis small, subspherical, with a small, oblique, curved horn. Pores irregular.
Dimensions.—Length of the shell (with seven joints) 0.2; length of the single joints, between 0.02 and 0.04, breadth 0.06 to 0.08.
Habitat.—Fossil in Sicily (Grotte, Caltanisetta).
20. Eucyrtidium stöhrii, n. sp.
Shell smooth, spindle-shaped, gradually diminishing towards both ends, with eight to ten distinct strictures. Nine to eleven joints of different lengths; the two or three middle joints—fifth, sixth, and seventh—longer and broader than the other joints; the broadest is the fifth joint, which is twice to three times as long as the first and last joints. Cephalis subspherical, with a conical horn of the same length. Terminal mouth strongly constricted, one-half or one-third as broad as the fifth joint. Pores small, regular, circular.
Dimensions.—Length of the shell (with ten joints) 0.22; length of the largest (fifth joint) 0.03, breadth 0.09.
Habitat.—Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.
21. Eucyrtidium scalarium, n. sp.
Shell smooth, slender, ovate, with nine to ten deep strictures, and ten to eleven separate step-like joints of different lengths. The sixth joint is the longest, twice as long as the fourth, and three times as long as the third and the last joint; the seventh and eighth joints are the broadest, one and a half times as broad as the wide mouth. Cephalis hemispherical, with a short pyramidal horn of the same length. Pores small and numerous, subregular, square, in regular transverse rows; six rows in the sixth joint, three rows in the last joint. (Somewhat similar to Spirocyrtis scalaris, Pl. 76, fig. 14, but ovate, not conical and not spiral.)
Dimensions.—Length of the shell (with eleven joints) 0.22, breadth 0.11; length of the last joint 0.01, of the sixth 0.03.
Habitat.—North Atlantic, Station 64, surface.
Subgenus 4. Acanthocyrtis, Haeckel, 1881, Prodromus, p. 437.
Definition.—Joints of the shell of very different lengths. Surface spiny.
22. Eucyrtidium tricinctum, n. sp. (Pl. 78, fig. 13).
Shell spiny, spindle-shaped, with three distinct strictures. Four joints of different lengths, the first and third half as long as the second and fourth; the third joint is the broadest, four times as
