Geological and Evolutionary Setting of the Biota. Geological Time and the Evolution of Early Life on Earth -- The Evolutionary Significance of the Chengjiang Biota -- The Discovery and Study of the Chengjiang Lagerstätte -- The Distribution and Geological Setting of the Chengjiang Lagerstätte -- The Taphonomy and Preservation of the Chengjiang Fossils -- The Paleoecology of the Chengjiang Biota -- Cambrian Lagerstätten -- Chengjiang Fossils. Algae -- Ctenophora -- Porifera -- Cnidaria -- Entoprocta -- Phoronida -- Brachiopoda -- Annelida -- Trochozoa of Uncertain Affinity -- Priapulida and Relatives -- Lobopodians -- Anomalocaridids -- Euarthropoda -- Chaetognatha -- Hemichordata -- Ambulacraria of Uncertain Affinity -- Chordata -- Bilateria of Uncertain Affinity -- Vetulicolians -- Animals of Uncertain Affinity -- Species Recorded from the Chengjiang Biota -- Phylogenetic Arrangement of Chapters.