1. Morphology and Systematics. - Comparative Morphology and Taxonomy. - Historical Perspectives on Radiolarian Taxonomy. - Modern Classificatory Systems. - Cytological and Fine Structure Contributions to Radiolarian Systematics. - A Perspective on the Current Status of Radiolarian Systematics. - 2. Radiolarian Fine Structure and Cellular Specialization. - Protozoan Cellular Specialization. - Fine Structure of Solitary Radiolaria. - Fine Structure of Colonial Radiolaria. - Fusule and Capsular Wall Fine Structure. - Host-Symbiont Fine Structure. - Parasitism. - Skeletal Structure and Morphogenesis. - Reproduction. - Fine Structure Synopsis. - 3. Physiology and Ecology. - Trophic Activity and Nutrition. - Intracapsular and Extracapsular Metabolic Differentiation. - Chemical Composition. - Predators. - Bioluminescence. - Symbiosis. - Motility and Cytoplasmic Streaming. - Radiolarian Longevity. - Abundance and Geographical Distribution. - General Ecological Perspectives. - 4. Paleoecology and Evolution. - Radiolaria in Geological Time. - Toward More Comprehensive Paleoecological Models. - Evolution. - A Perspective on Phylogeny Ecology and Biological Variability. - References. Language: English