The Evolution of the Metazoa

PrefaceIntroductionChapter 1. Cnidaria as the only Coelenterata The Systematic Position of the Spongiae The Systematic Position of the Ctenophora Cnidaria as the only Coelenterata Something about the Methods that can be Used in Connection with the Construction of the Natural Animal System The Significance of the Sessile Way of Life The Role of the Polymerization and of Subsequent Oligomerization during the Phylogeny The Validity of Watson's Rule for the InvertebratesChapter 2. The Previous Interpretations of Cnidaria The Origin of Cnidaria The Right Sequence of the Cnidaria Groups Why is there no Medusa Form in Anthozoa? The Primarily Solitary Polyps Appear in Anthozoa only Polymorphism Has Reached Its Climax in Hydrozoa The Regressive Development of the Intermediate Layer in Cnidaria The Morphologic Proofs of the New Interpretation of the Phylogeny of Cnidaria Muscular Tissue The Nervous System The Emunctory-Excretory Organ The Genital System The Alternation of Generations in Cnidaria The Digestive System The Skin and Cnidae Ontogeny (the Development of the Embryo) Asexual Reproduction and the Regeneration The Endosymbiotic Mononuclear AlgaeChapter 3. The Consequences of the New Interpretation of Cnidaria The New System of the Cnidaria The Rank and the Position of Cnidaria in the Animal System Discussion of the New Interpretation of the Evolution of Cnidaria The Probable Origin of Cnidaria The Larvae of "Cnidaria" A Comparison of Cnidaria Larvae with Other Larvae The Origin of the Turbellaria The Origin of the Acoelous Turbellaria The Relationship between Conjugation and Copulation The Point of Separation of the Evolutions of Infusoria and Eumctazoa The Origin of the Complex, Hypercellular Individualities Is the Plasmodial State of the Acoela a Primary Element? An Attempt to Reconstruct the Initial State of the Eumetazoa The Origin of the Middle Body Layer of the So-Called Mesoderm Two Difficulties of the Theory of Polykaryonts Can Cleavage be Really Considered as a Proof of the Colonial Theory? The Basic Principles that should be Used in a Reform of the Whole Animal System Evolution Generally had a Progressive TrendChapter 4. The Classification of the Animal World and the New Genealogical Tree General Premises The Limit between the Plant and the Animal Worlds The System of the Protozoa The Transition from the Protozoa to the Metazoan State There Are No Well-Warranted Mesozoa The Classification of Metazoa The Parazoa as an Independent Subregnum The Eumetazoa and their Subdivisions The Elimination of the Terms Coelenterata-Coelomata The Coelomata as a Taxonomic Unit The First Phylum of the Eumetazoa: The Ameria The Transition from the Amerous to the Polymerous State The Problem of Justification of the High Taxons: Protostomia-Deuterostomia The Classes of the Polymeria The Phylum Oligomeria and Its Classes The Sphere of the Phylum Oligomeria The Problem of the Inclusion of the Sipunculida into the Phylum Oligomeria The Oligomeria as the Initial Form for the Evolution of the Chordonia The Fourth and the Last Phylum of the Eumetazoa: Chordonia The Probable Origin of the Chordonia A Comparison of the Present Attempt to Derive the Chordonia from the Ancestral Form Resembling the Present Day Enteropneusta with the Similar Attempt Made by Hans Steiner The Genealogical Tree of the Chordonia The Genealogical Tree of the Entire Animal World An Attempt to Unify the Animal SystemBibliographyIndex