Dimensions.—Length of the three joints, a 0.014, b 0.018, c 0.076; breadth, a 0.023, b 0.044, c 0.073.
Habitat.—Fossil in the chalk of Northern Germany; Brunswick (Zittel).
2. Theocampe pirum, Haeckel.
Shell ovate, smooth. Length of the three joints = 3 : 5 : 15, breadth = 6 : 10 : 16. Cephalis hemispherical. Thorax truncate conical. Abdomen inflated, subspherical, three times as broad as the constricted mouth. Pores of nearly equal size, regular, circular in the thorax alternating, in the abdomen disposed in five to six transverse, widely distant rows.
Dimensions.—Length of the three joints, a 0.015, b 0.025 c 0.075; breadth, a 0.03, b 0.05, c 0.08.
Habitat.—Fossil in the Tertiary rocks of Barbados.
3. Theocampe stenostoma, n. sp. (Pl. 66, fig. 23).
Shell about ovate, smooth. Length of the three joints = 3 : 4 : 3, breadth = 6 : 8 : 9. Cephalis hemispherical, large. Thorax and abdomen short, barrel-shaped. Both strictures deep. Abdomen three times as broad as the constricted mouth. Pores of equal size, regular, circular, disposed in oblique rows.
Dimensions.—Length of the three joints, a 0.03, b 0.04, c 0.03; breadth, a 0.06, b 0.08, c 0.09.
Habitat.—North Pacific, Station 244, depth 2900 fathoms.
4. Theocampe nucula, Haeckel.
Shell nearly ovate, rough. Length of the three joints = 3 : 5 : 3, breadth = 4 : 7 : 6. Cephalis hemispherical, large. Thorax and abdomen inflated. Both strictures deep. Thorax broader than the short abdomen, and twice as broad as the constricted mouth. Pores of equal size, regular, circular, regularly disposed in transverse rows: three in the cephalis, six in the thorax, and three in the abdomen.
Dimensions.—Length of the three joints, a 0.03, b 0.05, c 0.03; breadth, a 0.04, b 0.07, c 0.06.
Habitat.—Tropical Atlantic, Station 347, depth 2250 fathoms; also fossil in Barbados.
5. Theocampe cryptoprora, Haeckel.
Shell ovate, thin-walled, smooth, without external strictures, but with two distinct internal annular septa. Length of the three joints = 2 : 7 : 4, breadth = 3 : 7 : 6. Cephalis, large, subspherical,