broad as the strongly constricted mouth. Spines irregularly scattered over the lower half of the shell, increasing in size towards the mouth. Pores subregular, circular.
Dimensions.—Length of the shell (with four joints) 0.25. Length of the single joints, a 0.03, b 0.08, c 0.04, d 0.09; breadth (of the third joint) 0.1.
Habitat.—Western Tropical Pacific, Station 225, depth 4475 fathoms.
23. Eucyrtidium armatum, n. sp. (Pl. 78, fig. 14).
Shell spiny, spindle-shaped, with three distinct strictures. Four joints of different lengths, the second and third joints of the same length, shorter than the fourth joint; the third joint is the broadest, four times as broad as the strongly constricted mouth. The latter, as well as the conical cephalis, is armed with an irregular bunch of strong conical spines, while numerous smaller spines are scattered over the whole surface. Pores irregular, roundish, double-contoured.
Dimensions.—Length of the shell (with four joints) 0.2. Length of the single joints, a 0.02, b 0.05, c 0.05, d 0.08; breadth (of the third joint) 0.1.
Habitat.—Western Tropical Pacific, Station 224, depth 1850 fathoms.
24. Eucyrtidium conostoma, n. sp. (Pl. 78, fig. 16).
Shell spiny, spindle-shaped, with four distinct strictures. Five joints of different lengths, having the proportion = 1 : 2 : 3 : 6 : 10. The fourth joint is the broadest, inflated, twice as broad as long. Cephalis small, with a conical horn of the same length. Fifth joint inversely conical, with a narrow mouth, broader than the cephalis. Short conical spines are scattered over the whole surface. Pores subregular, circular.
Dimensions.—Length of the shell (with five joints) 0.22. Length of the single joints, a 0.01, b 0.02, c 0.03, d 0.06, e 0.1; breadth (of the fourth joint) 0.09.
Habitat.—Central Pacific, Station 265, depth 2900 fathoms.
25. Eucyrtidium ehrenbergii, n. sp. (Pl. 78, fig. 15).
Shell spiny, spindle-shaped, with four distinct strictures (the first and the fourth are by a mistake not distinctly figured). Five joints of different lengths, having the proportion = 2 : 3 : 4 : 2 : 5. The third joint is the broadest, twice as broad as long, and twice as broad as the constricted mouth. Whole surface covered with strong spines. Pores irregular, roundish.
Dimensions.—Length of the shell (with five joints) 0.16. Length of the single joints, a 0.02, b 0.03, c 0.04, d 0.02, e 0.05; breadth (in the third joint) 0.08.
Habitat.—Western Tropical Pacific, Station 220, depth 1100 fathoms.
26. Eucyrtidium ovatum, n. sp.
Shell spiny, inversely ovate, with five sharp strictures. Six joints of different lengths, having the proportion = 1 : 3 : 2 : 1 : 1 : 3. The third joint is the broadest, three times as broad as the con-
