File:EB1911 Radiolaria (2).jpg

English: Radiolaria: 1. Lithocircus annularis, Hertwig; one of the Monopylaea. Whole animal in the living state (optical section); a, nucleus; b, wall of the central capsule; c, yellow cells; d, perforated area of the central capsule (Monopylaea). 2. Cystidium inerme, Hertwig; one of the Monopylaea. Living animal. An example of a Monopylaeon destitute of skeleton. a, nucleus; b, capsule-wall; c, yellow cells in the extracapsular protoplasm. 3. Carpocanium diadema, Haeck.; optical section of the beehive-shaped shell to show the form and position of the protoplasmic body. a, the tri-lobed nucleus; b, the siliceous shell; c, oil-globules; d, the perforate area (pore-plate) of the central capsule. 4. Coelodendrum gracillimum, Haeck.; living animal, complete; one of the Tripylaea. a, the characteristic dark pigment (phaeodium) surrounding the central capsule b. The peculiar branched siliceous skeleton, consisting of hollow fibres, and the expanded pseudopodia are seen. 5. Central capsule of one of the Tripylaea, isolated, showing a, the nucleus; b, c, the inner and the outer laminae of the capsule wall; d, the chief or polar aperture; e, e, the two secondary apertures. 6, 7. Acanthometra claparedei, Haeck. 7 shows the animal in optical section, so as to exhibit the characteristic meeting of the spines at the central point as in all Acanthometridea; 6 shows the transition from the uninuclear to the multinuclear condition by the breaking up of the large nucleus. a, small nuclei; b, large fragments of the single nucleus; c, wall of the central capsule; d, extracapsular jelly (not protoplasm); e, peculiar intracapsular yellow cells. 8. Spongosphaera streptacantha, Haeck.; one of the Peripylaea. Siliceous skeleton not quite completely drawn on the right side. a, the spherical extracapsular shell (compare fig. III. 17), supporting very large radial spines which are connected by a spongy network of siliceous fibres. 9. Aulosphaera elegantissima, Haeck.; one of the Phaeodaria. Half of the spherical siliceous skeleton.