Dimensions.—Length of the three joints, a 0.02, b 0.02, c 0.07; breadth, a 0.025, b 0.035, c 0.045.

Habitat.—Fossil in Barbados.

13. Theocampe costata, n. sp. (Pl. [66], fig. 24).

Shell almost ovate, with two sharp strictures. Length of the three joints = 2 : 4 : 8, breadth = 3 : 5 : 7. Cephalis hemispherical. Thorax twice as large, also hemispherical, both with regular, circular, quincuncial pores. Abdomen broader, with numerous longitudinal ribs, alternating with longitudinal rows of larger pores. Mouth constricted, half as broad as the thorax.

Dimensions.—Length of the three joints, a 0.02, b 0.04, c 0.08; breadth, a 0.03, b 0.05, c 0.07.

Habitat.—Indian Ocean, Sunda Straits (Rabbe), surface.

14. Theocampe cryptocephala, Haeckel.

Eucyrtidium cryptocephalum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi. fig. 11.

Shell ovate, rough, with two distinct strictures. Length of the three joints = 1 : 2 : 4, breadth = 1 : 4 : 5. Cephalis subspherical, its lower half hidden in the campanulate thorax. Abdomen subspherical, twice as broad as the constricted mouth. Pores subregular, circular, quincuncial, twice as broad in the abdomen as in the thorax.

Dimensions.—Length of the three joints, a 0.02, b 0.04, c 0.07; breadth, a 0.025, b 0.07, c 0.09.