Page:Scientific results HMS Challenger vol 18 part 2.djvu/553

Rh 9. Theocapsa linnæi, n. sp. (Pl. 66, fig. 13).

Shell slender, subcylindrical, rough with two slight strictures. Length of the three joints = 1 : 3 : 6, breadth = 1 : 4 : 4. Cephalis hemispherical, with a pyramidal horn of twice the length (sometimes, as in the specimen figured, one or two small accessory horns occur at its base). Thorax hemispherical, thick-walled. Abdomen nearly cylindrical, twice as long as the thorax, thin-walled, with a hemispherical, rounded basal pole. The specimen figured is an abnormal one, with some deformities on the irregular abdomen; in numerous other specimens the abdomen is cylindrical, regular. Pores of the thorax and abdomen equal, very small and numerous, regular, circular, three to four times as broad as the bars.

Dimensions.—Length of the three joints, a 0.02, b 0.05 to 0.06, c 0.1 to 0.12; breadth, a 0.03, b 0.06 to 0.07, c 0.07 to 0.08.

Habitat.—Cosmopolitan; Atlantic, Indian, and Pacific Oceans; many Stations at various depths.

10. Theocapsa forskalii, n. sp. (Pl. 66, fig. 9).

Shell slender, subcylindrical, smooth, with two slight strictures. Length of the three joints = 1 : 1 : 3, breadth = 1 : 2 : 2. Cephalis hemispherical, with a conical horn of half the length. Abdomen three times as long as the thorax, of the same breadth, with the same irregular, roundish pores, large and small intermingled. Basal pole rounded.

Dimensions.—Length of the three joints, a 0.02, b 0.03, c 0.09; breadth, a 0.03, b 0.06, c 0.06.

Habitat.—North Atlantic, Canary Islands, Station 353, depth 2965 fathoms.

11. Theocapsa wolffii, n. sp. (Pl. 66, fig. 14).

Shell slender, spindle-shaped very thick-walled, rough, without external strictures, but with two broad internal girdles. Length of the three joints = 2 : 3 : 15, breadth = 4 : 5 : 7. Cephalis with a short horn of the same length, conical. Abdomen five times as long as the thorax, with the same subregular, circular pores. Basal pole inversely conical, with some larger, elongate pores.

Dimensions.—Length of the three joints, a 0.02, b 0.03, c 0.15; breadth, a 0.04, b 0.05, c 0.07.

Habitat.—Mediterranean, Crete, depth 1620 fathoms (Spratt).

12. Theocapsa pallasii, n. sp.

Shell subovate, thorny, with two slight strictures. Length of the three joints = 1 : 2 : 3, breadth = 1 : 2 : 3. Cephalis ovate, with a pyramidal horn of the same length. Thorax and abdomen with subregular, circular pores of medium size. Basal pole hemispherical. (Differs from Theocapsa mülleri, Pl. 66, fig. 7, mainly in the larger number and smaller size of the regular, quincuncial pores.)

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

Habitat.—Tropical Atlantic, Station 342, depth 1445 fathoms.