Page:Scientific results HMS Challenger vol 18 part 2.djvu/180

1056 2. Zygospyris equus, n. sp. (Pl. 83, fig. 16).

Shell subspherical, rough, with slight sagittal stricture. Pores small and numerous, subregular circular; no larger annular pores. Apical horn cylindrical, half as long as the shell. Two pectoral feet somewhat smaller than the two tergal feet, about as long as the shell, slightly divergent, cylindrical. The distal ends of the feet and of the horn form an ovate, dimpled and spinulate cone.

Dimensions.—Shell 0.06 long, 0.09 broad; horn 0.04 long, feet 0.06 long.

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

Definition.— with two pairs of lateral feet and three coryphal horns.

The genus Elaphospyris differs from the preceding Zygospyris, its ancestral form, in the possession of three coryphal horns (one odd apical and two paired frontal horns), and therefore bears to it the same relation that Triceraspyris does to Tripospyris among the Tripospyrida.

Definition.—Feet simple, not branched nor forked.

1. Elaphospyris heptaceros, Haeckel.

Ceratospyris heptaceros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx. fig. 2.

Giraffospyris heptaceros, Haeckel, 1881, Prodromus, p. 442.

Shell nut-shaped, tuberculate, with slight sagittal stricture and subregular circular pores. Basal plate with four large pores. Apical horn small, conical, shorter than the two curved lateral horns, which are as long as the shell. Caudal and sternal feet small, conical, straight. Two pectoral feet slender, divergent, S-shaped, about as long as the shell.

Dimensions.—Shell 0.05 long, 0.07 broad; horns and feet 0.02 to 0.08 long.

Habitat.—Fossil in Barbados.

2. Elaphospyris capricornis, n. sp.

Shell nut-shaped, spiny, with slight sagittal stricture and numerous small circular pores. Basal plate with four large pores. Three horns slender, simple, about as long as the shell, the middle one straight, the two lateral curved. Four feet of nearly equal size, slender, curved, divergent, simple, twice as long as the shell and the horns.

Dimensions.—Shell 0.07 long, 0.09 broad; horns 0.08 long, feet 0.15 long.

Habitat.—Central Pacific, Station 274, depth 2750 fathoms.