Page:Scientific results HMS Challenger vol 18 part 1.djvu/225

Rh ; on its inside often numerous oval nucleoli. In the movable protoplasmic network between the large alveoles a considerable number of large yellowish or orange oil-globules. Extracapsular jelly-envelope very thin, contains small yellow bodies (zooxanthellæ). (Compare the accurate description of this Mediterranean species in my monograph and in Hertwig's work.) In the Canary Islands I found very often a large variety of it, of double and triple the size, distinguished by the delicate orange colour of the intracapsular oil-globules. This may be distinguished as Thalassolampe aurantiaca.

Dimensions.—Diameter of the whole jelly-sphere 2 to 4 mm., of the central capsule 2 to 3 mm., of its nucleus 0.2 to 0.4 mm.

Habitat.—Mediterranean, Messina, Haeckel, Hertwig; Canary Islands, Lanzerote, Haeckel; surface.

2. Thalassolampe maxima, n. sp. (Pl. 1, fig. 2).

Spherical body quite pellucid, like a glass globule, colourless. Central capsule with a moderately thick, but quite transparent, structureless membrane, its diameter ten to twelve times as large as that of the central spherical nucleus. Wall of the vesicular nucleus thick, perforated by fine pore-canals; on its inside numerous small spherical nucleoli. No large oil-globules in the movable protoplasmic network between the large alveoles. Extracapsular jelly-envelope very thin, containing no yellow bodies. This differs from the preceding nearly allied species in the want of the intracapsular oil-globules and of the extracapsular yellow bodies. It possesses the largest central capsule of all known Radiolaria. I found them living and floating in water taken from the surface of the Indian Ocean by a bucket.

Dimensions.—Diameter of the whole jelly-body 12 to 15 mm., of the central capsule 10 to 12 mm., of the nucleus 0.8 to 1.2 mm.

Habitat.—Indian Ocean, near the Maldive Islands, Haeckel, 1882, surface.

Definition.—Thalassicollida without extracapsular alveoles, but with large roundish or globular alveoles within the central capsule, with a papillate or branched nucleus in its centre.

The genus Thalassopila has, like Thalassolampe, a voluminous foamy central capsule, inflated by numerous large alveoles; but it differs in the complicated form of the nucleus, which is like that of Thalassophysa, and is either branched or occupied by conical or roundish papillæ.

1. Thalassopila cladococcus, n. sp. (Pl. 1, fig. 3).

Spherical body dark-spotted, with a thin yellowish jelly-envelope. Central capsule with a thick and firm membrane, perforated by pores; its diameter three times that of the central nucleus,