Page:Scientific results HMS Challenger vol 18 part 2.djvu/546

1422 4. Lophocorys quadricornis, n. sp.

Shell rough, slenderly ovate, with two distinct strictures. Length of the three joints = 2 : 4 : 2, breadth = 2 : 4 : 3. Cephalis ovate, with four very stout, three-sided prismatic horns; the largest is as long as the thorax and vertical upon the apex, the three smaller are as long as the cephalis and diverge upwards from the base of the former. Thorax ovate, with large, irregular, roundish pores, which are three to four times as broad as the small, circular pores of the first and the third joint. Constricted mouth half as broad as the thorax.

Dimensions.—Length of the three joints, a 0.045, b 0.085, c 0.04; breadth, a 0.035, b 0.075, c 0.06.

Habitat.—South Atlantic, Station 332, depth 2200 fathoms.

5. Lophocorys bovicornis, n. sp. (Pl. 69, fig. 12).

Shell rough, subovate, with two deep strictures. Length of the three joints = 1 : 2 : 3, breadth = 1 : 3 : 4. Cephalis subspherical, with two divergent, curved horns of different lengths. Thorax campanulate, with small, circular pores. Abdomen subspherical, truncate at both poles, twice as broad as the constricted mouth, thorny, with very large, circular pores, four to six times as broad as those of the smaller thorax.

Dimensions.—Length of the three joints, a 0.03, b 0.06, c 0.09; breadth, a 0.04, b 0.09, c 0.12.

Habitat.—Central Pacific, Station 270, depth 2925 fathoms.

Definition.— (vel Tricyrtida eradiata aperta) with ovate abdomen, broader than the constricted mouth. Cephalis without horn.

The genus Theocampe differs from the two preceding genera in the absence of horns on the cephalis, and may, therefore be derived from Theocorys by reduction of the apical horn. It bears to the latter the same relation as Tricolocampe does to Theocyrtis.

Definition.—Pores of the thorax and the abdomen of nearly equal size and similar form.

1. Theocampe ehrenbergii, Haeckel.

Dictyomitra ehrenbergii, Zittel, 1876, Zeitschr. d. deutsch. geol. Gesellsch., p. 82, Taf ii. fig. 5.

Shell ovate, smooth. Length of the three joints = 2 : 3 : 13, breadth = 4 : 7 : 12. Cephalis hemispherical. Thorax truncate, conical. Abdomen inflated, nearly spherical, twice as broad as the constricted mouth. Pores of nearly equal size and form, small, regular, circular.