Habitat.—Central Pacific, Station 266, depth 2750 fathoms.
Subgenus 2. Lithomitrissa, Haeckel.
Definition.—All (or the majority) of the joints of the shell with several transverse rows of pores, in variable number.
7. Lithomitra cylindrica, n. sp.
Shell cylindrical, smooth, with twelve to sixteen internal septal rings (without external strictures). On each joint two transverse rows of small, regular, circular pores. The hemispherical cephalis also has two rows of pores. Each joint is twice as broad as long.
Dimensions.—Length of the shell (with sixteen joints) 0.3; length of each joint 0.02, breadth 0.04.
Habitat.—South Pacific, Station 297, depth 1775 fathoms.
8. Lithomitra costata, Haeckel.
Dictyomitra costata, Stöhr, 1880, Palæontogr., vol. xxvi. p. 101, Taf. iii. fig. 23.
Shell with longitudinal ribs, in the upper half conical, in the lower half cylindrical, with six to eight slight strictures. Small, circular pores in regular transverse rows; three rows in each upper joint, two rows in each lower joint (the last joints sometimes confluent).