Dimensions.—Length of the shell (with four joints) 0.18, breadth 0.12. Length of the single joints, a 0.03, b 0.04, c 0.05, d 0.06.

Habitat.—Central Pacific, Station 272, depth 2600 fathoms.

6. Cyrtocapsa diploconus, n. sp. (Pl. [78], fig. 6).

Shell rough, doubly conical, with three annular septa. Length of the four joints = 3 : 4 : 4 : 8. The third joint is the broadest, two and a half times as broad as long; the fourth is inversely conical, acute. Cephalis hemispherical, with a pyramidal horn of the same length. Pores irregular, roundish.

Dimensions.—Length of the shell (with four joints) 0.19, breadth 0.1. Length of the single joints, a 0.03, b 0.04, c 0.04, d 0.08.

Habitat.—Tropical Atlantic, Station 347, depth 2250 fathoms.

7. Cyrtocapsa fusulus, n. sp. (Pl. [78], fig. 7).

Shell smooth, spindle-shaped, with three distinct strictures. Length of the four joints = 1 : 1 : 4 : 3. The third joint is the broadest, somewhat longer than broad. The fourth joint is inversely conical. Cephalis hemispherical, with a coronal of large, ovate pores, and a pyramidal, sulcate, oblique horn of twice the length. Pores regular, circular.

Dimensions.—Length of the shell (with four joints) 0.18, breadth 0.07. Length of the single joints, a 0.02, b 0.02, c 0.08, d 0.06.

Habitat.—South Pacific, Station 295, depth 1500 fathoms.