General Remarks. Main Functions of the Serosal Membranes -- Common Organization of the Pleura, Peritoneum and Pericardium -- Mesothelial Cells. Surface Membrane Specializations -- Stomata -- Milky Spots -- Transport Across the Serosal Membranes -- Secretory Functions of the Mesothelium with Special Reference to Fibrinolysis -- Healing and Regeneration. Serosal Adhesions -- Response to Inflammation -- Effects of Peritoneal Dialysis -- Material and Methods -- Material (A) Animals (B) Human -- Methods -- Results -- General Organization of the Human and Animal Serosal Membranes -- Development of the Pleura -- Horseradish Peroxidase Transfer Across the Serosal Membranes -- The Injured Serosal Membranes and Their Response -- Discussion -- Normal Structure of the Serosal Membranes -- Prenatal and Postnatal Development of the Pleura -- Transport across the Serosal Membranes -- Injured Serosal Membranes and Their Recovery -- Summary -- References -- Subject Index. (will follow)