Page:Scientific results HMS Challenger vol 18 part 2.djvu/294

1170 lamellar or lanceolate feet, which are twice to three times as long as the shell, parallel and vertical. (Very similar to Petalospyris flabellum, &c., Ehrenberg, 1875, loc. cit., Taf. xxii. figs. 6-8, but without any trace of sagittal ring or columella.)

Dimensions.—Shell 0.05 to 0.08 diameter, feet 0.15 to 0.25 long.

Habitat.—Central Pacific, Stations 266 to 268, depth 2700 to 2900 fathoms.

Definition.—Shell spiny, covered with numerous spines or thorns (besides the feet and the apical horn).

6. Halicalyptra spinosa, n. sp.

Shell spiny, ovate, inflate in the apical half. Pores irregular polygonal, four to eight times as broad as the bars. Peristome constricted, half as broad as the shell, with nine slender divergent feet, which like the apical horn are curved, twice to three times as long as the shell and five to ten times as long as the numerous bristles of the surface.

Dimensions.—Shell 0.08 long, 0.06 broad; feet 0.15 to 0.25 long.

Habitat.—Central Pacific, Station 271, depth 2425 fathoms.

7. Halicalyptra castanella, n. sp.

Shell spiny, nearly spherical. Pores irregular roundish. Peristome constricted, scarcely one-third as broad as the shell, with twelve to twenty slender, widely divergent feet, which like the horn are irregularly curved, and longer than the shell. (Very similar to certain forms of the Phæodarium Castanella, Pl. 113, fig. 2.)

Dimensions.—Shell 0.13 diameter, feet 0.15 to 0.18 long.

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

Definition.— (vel Monocyrtida multiradiata aperta) without radial ribs in the wall of the campanulate or ovate shell. Mouth with a corona of radial feet. Apex without horn.

The genus Carpocanistrum differs from the similar preceding Halicalyptra in the loss of the apical horn. It is very nearly related to the Dicyrtid Carpocanium and may be easily confounded with it. But in the latter the uppermost part of the shell-cavity includes a rudimentary cephalis with a cortinar septum, whilst in Carpocanistrum