1. Collozoum inerme, Haeckel (Pl. 3, figs. 10-12).
Collozoum inerme, Cienkowski, 1871, Archiv. f. mikrosk. Anat., vol. vii. p. 376, Taf. xxix. figs. 18-36.
Collozoum inerme, R. Hertwig, 1876, Histologie der Radiol., p. 12, Taf. i., ii.
Collozoum inerme, R. Hertwig, 1879, Organismus d. Radiol., p. 31, Taf. iii. fig. 12.
Sphærozoum inerme, J. Müller, 1856, Monatsber. d. k. Akad. d. Wiss. Berlin, p. 478; Abhandl., p. 54.
Sphærozoum bicellulare, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 54, Taf. viii. fig. 5.
Thalassicolla punctata, Huxley (pro parte), 1851, Ann. and Mag. Nat. Hist., ser. 2, vol. viii. p. 433.Central capsules spherical, with thin, simple-edged membrane, with one single oil-globule in the centre. (If the capsules multiply by division, the spherical form becomes violin-shaped, constricted in the middle; and in this condition the number of oil-globules increases; but in the ordinary mature state the capsule of this species remains spherical, and its oil-globule solitary. In quite young capsules the oil-globules are wanting; Pl. 3, fig. 12.)
Dimensions.—Diameter of the central capsules 0.04 to 0.16.
Habitat.—Cosmopolitan, common in all warmer seas (Mediterranean, Atlantic, Indian, and Pacific), surface.
2. Collozoum nostochinum, n. sp.
Central capsules spherical, very large, opaque, distended with red pigment-granules and with very numerous (two hundred to three hundred) small oil-globules. Membrane thick, double-edged.
Dimensions.—Diameter of the central capsules 0.3 to 0.5.
Habitat.—Indian Ocean, off Socotra, surface, Haeckel.
3. Collozoum volvocinum, n. sp.
Central capsules spherical, very large, opaque, containing a great number (ten to thirty) of large oil-globules, and between them densely packed masses of dark pigment. Membrane thick, double-edged. This species differs from Collozoum inerme, mainly by the great size of the central capsules (three to five times as big as in the former) and the great number of oil-globules in them.
Dimensions.—Diameter of the central capsules 0.2 to 0.3.
Habitat.—Central Pacific, Station 272, surface.
Subgenus 2. Colloprunum, Haeckel.
Definition.—Form of the central capsules ellipsoidal, with one prolonged axis.
4. Collozoum ovatum, n. sp.
Central capsules ovate or ellipsoidal, its longer diameter twice to three times as large as the shorter. In the centre of every capsule one single oil-globule.
