Shell subcylindrical, rough, with seven slight strictures. The two or three middle joints half as long as the two preceding and the two following joints. Cephalis small, subspherical. Pores small, in subregular, transverse rows, on the fifth and sixth joints only two rows, on the second, third, seventh, and eighth joints four to five rows.
Dimensions.—Length of the shell (with eight joints) 0.27; length of the fifth and sixth joints 0.17, of the others 0.03 to 0.04; breadth 0.08.
Habitat.—Fossil in Tertiary rocks of Sicily, Grotte (Stöhr).
14. Lithomitra infundibulum, n. sp. (Pl. [79], fig. 5).
Shell in the upper half subconical, in the lower half subcylindrical, rough, with four slight strictures. Cephalis hemispherical. Thorax conical. Abdomen subcylindrical, three-jointed. Pores of the second, third, and fourth joints funnel-shaped, with very small inner, and larger double-contoured outer aperture; on the thorax twelve transverse rows, on the third and fourth joints five rows. Fifth joint with irregular, polygonal pores.
Dimensions.—Length of the shell (with five joints) 0.2; length of the thorax 0.06, breadth 0.08; length of each abdominal joint 0.04, breadth 0.08.
Habitat.—Central Pacific, Station 271, depth 2425 fathoms.
Genus 647. Eucyrtidium,[[264]] Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.
Definition.—Stichocorida (vel Stichocyrtida eradiate aperta) with ovate or spindle-shaped shell, the mouth of which is constricted, but not prolonged into a tube. Cephalis with a solid horn.
The genus Eucyrtidium (as here stated in the definition) and the three following nearly allied genera differ from the preceding Stichocorida in the more or less constricted mouth, and the consequent ovate or spindle-form of the multiarticulate shell. The middle joints of the latter are broader than the upper and the lower joints. In the earlier definition given in my Monograph (1862, pp. 312 to 320), the genus had a much wider sense; but the very large number of species since detected requires a more strict definition. Ehrenberg confounded in his genus Eucyrtidium a large number of very different Cyrtoidea. In his last works (1872, 1875) he described not less than one hundred and eleven species, fifty-five fossil and fifty-six living (eight fossil species being yet living). But, in reality, these one hundred and three species belong to twenty or twenty-two very different genera of Cyrtoidea.