Subgenus 2. Pentalacorys, Haeckel, 1881, Prodromus, p. 436.
Definition.—Peristome armed with five feet, one of which is odd and occipital, the other four paired and lateral.
3. Alacorys pentacantha, Haeckel.
Podocyrtis pentacantha, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvii. fig. 1.
Shell rough, with slight collar stricture. Length of the three joints = 1 : 2 : 3, breadth = 1 : 4 : 6. Cephalis subspherical, with a rudimentary conical horn. Thorax campanulate, with subregular, circular, quincuncial pores. Abdomen wider, campanulate, with a small number of very large and irregular, roundish holes. From the peristome descend five stout conical feet, which are slightly curved and divergent, nearly as long as the shell.
Dimensions.—Length of the three joints, a 0.02, b 0.05, c 0.06; breadth, a 0.025, b 0.08, c 0.11.
Habitat.—Fossil in Barbados.
4. Alacorys bismarckii, n. sp. (Pl. [65], fig. 3).
Shell spiny, with distinct collar stricture. Length of the three joints = 1 : 4 : 5, breadth = 2 : 7 : 10. Cephalis hemispherical, with a very stout, dimpled, conical horn of the same length. Thorax campanulate, spiny, with regular, circular pores. Abdomen wider, campanulate, with larger conical spines, and a small number of irregular, roundish, very large holes. From the peristome descend, nearly vertically, five very large cylindrical feet, nearly twice as long as the shell; they are S-shaped, curved, spinulate in the distal half, and armed at the proximal base with two stout conical spines, the smaller of which is directed inwards, the larger curved upwards. Dedicated to Prince Otto von Bismarck, the Reconstructor of the German Empire.
Dimensions.—Length of the three joints, a 0.02, b 0.08, c 0.1; breadth, a 0.04, b 0.14, c 0.2.