Eucyrtidium imbricatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi. fig. 22.
Shell thick-walled, subcylindrical, with longitudinal ribs, slightly dilated in the middle, with ten to twelve subequal joints. On the lower edge of each joint a single row of small circular pores. No external strictures. This and the following species (though separated by Ehrenberg as four different species) may be united.
Dimensions.—Length of the shell (with ten joints) 0.11; length of each joint 0.01 to 0.012, breadth 0.04.
Habitat.—Fossil in Barbados.
2. Lithomitra acephala, Bütschli.
Lithomitra acephala, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.
Eucyrtidium acephalum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi. fig. 5.
Eucyrtidium obstipum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi. fig. 17.
Shell nearly cylindrical, smooth, thick-walled, with twelve to sixteen subequal joints. On each joint a single row of small circular pores. No external strictures. Scarcely differing from the preceding species; the joints are broader and shorter, the cephalis is larger (by union of some joints?), and the ribs of the surface less distinct.
Dimensions.—Length of the shell (with twelve joints) 0.1; length of each joint 0.006 to 0.009, breadth 0.04.